Step by step tuning Alpine A310

[sucahyo]

This is my method for tuning Alpine A310. Feel free to post your story when tuning this unique car.

Part list:
Stage 3 Turbo, oil changed, racing exhaust, port polish, engine balance
Stage 3 Weight mod, rollcage, racing suspension, brake controller, Variable LSD
S3/S3 tire

In case you miss it:
no wing
rollcage

When tuning I want:
no Aids - no TCS, no ASM
no balast mod


Initial suspension value:
Suspension
-Spring Rate: 4.0 / 3.0
-Ride Height: 180 / 180
-Bound: 10 / 10
-Rebound: 10 / 10
-Camber: 0.0 / 0.0
-Toe: 0 / 0
-Stabilizers: 1 / 1

LSD
-Initial: 5
-Acceleration: 30
-Deceleration: 15

Downforce
Amount: -- / --

Driving Aids
-ASM Oversteer: 0
-ASM Understeer: 0
-TCS: 0

Brake Controller
-Brakes: 1 / 1

Transmission
- --

Ballast
-Weight: 0
-Location: 0


Tuning Location:
Apricot Hill


tuning
When I first driving this car, I felt soo much oversteer that even without steering, the car will try to continue turning. So as usual, my first step is to make the car more understeer using stabilizer:
Stabilizer: 7/1


Then I drive it again. The car still feel oversteer, the rear tire still slipping. I try to use spring rate for this. Since I believe stronger spring rate have more traction I try many different rear spring rate value. And finally use:
Spring rate: 4.0/10.0


It seem most people won't use this kind of extreme combination, but I don't know other more suited method to increase rear tire grip. Using camber to reduce front tire traction is not what I want to do and I don't like to use tire stagger. Downforce would be ineffective at low speed, ballast will reduce the car performance. Aids will add more trouble than helping. LSD wouldn't help much.

I feel using spring rate to increase rear tire traction a bit special. I will only use this on GT series.

After this the car feel more planted. And then I notice that when braking, the car want to go straight. I try to use damper for this and finally use:
Damper:
-Bound: 10 / 1
-Rebound: 10 / 1


When using this value, I still don't know what the car reaction is if I apply throttle in the middle of cornering. But seeing the car have no problem for that I keep using this value. Braking understeer is less now, but still present, maybe I can use BBC to cure that but I run out of time, so I just add little tweak to reduce rear slipping more by using my usual reduce rear drift by toe:
Toe: 0/-4


Compare to the first state, the car is now more drivable, where I can complete many lap without much drama. At this state spinning the car require an effort, not a mistake .

Additional tuning maybe required to get more performance from this car. But if you just want to get a safe drive, this will do.

Final setting:
Suspension
-Spring Rate: 4.0 / 10.0
-Ride Height: 180 / 180
-Bound: 10 / 1
-Rebound: 10 / 1
-Camber: 0.0 / 0.0
-Toe: 0 / -4
-Stabilizers: 7 / 1

LSD
-Initial: 5
-Acceleration: 30
-Deceleration: 15

Downforce
Amount: -- / --

Driving Aids
-ASM Oversteer: 0
-ASM Understeer: 0
-TCS: 0

Brake Controller
-Brakes: 1 / 1

Transmission
- --

Ballast
-Weight: 0
-Location: 0

 

[Scaff]

I will give those a try as and when I can, for interest I did a set-up on the same car a while ago for BESTuners

https://www.gtplanet.net/forum/showpost.php?p=2063234&postcount=311

The full write-up and pictures can be seen in the link above, this particular tune is designed to keep the basic tail-happy characteristics of the car in place, but in a controllable manner. I don't personally agree that with a RR car you can 'tune' out the natural behaviour of the car without destroying its charm. This particular set-up has also been used to win a few 200pt events, something I am quite proud of and does speak as to the possibilities in the car itself.



Spec

202bhp@6,250rpm
173ft/lbs@5,300rpm
902kgs

0-30 – 2.18 secs
0-60 – 5.52 secs
1-100 – 12.78 secs
0-100-0 – 16.78 secs

1/4 Mile – 13.773 secs @ 103mph
Top Speed – 159.07mph




Modifications

Racing Exhaust
Racing Chip
NA Tune Stage 2
R3 Tyres for the lap, N2 and S2 tyres for fun (front & back)
Racing Brakes
Brake Balance Controller
Racing Suspension
Fully Customised Transmission
Triple Plate Clutch
Racing Flywheel
Fully Customised LSD
Weight Reduction Stage 1
Port Polish
Engine Balance
Oil Change




Settings
All are shown Front then Rear

Spring Rates = 7.0 / 5.5
Ride Height = 115 / 120
Damper
Bound = 2 / 3
Rebound = 4 / 5
Camber = 2.0 / 1.3
Toe = 0 / -1
Stabilisers = 3 / 2

LSD = 10/40/20

Brake Balance = 4 / 3

Gearbox = Auto 9 (adjust as required)


Regards

Scaff

 

[sucahyo]

I will try yours as well .

If you still remember, can you explain step by step on how you came up with that setting?

Even though this car has the same engine layout as RUF CTR Yellow bird. I tune this car differently from RUF CTR Yellow Bird. I feel RUF CTR has strong understeer in mid corner where A310 feel has strong oversteer.

 

[sucahyo]

I have tried your car Scaff. It show different tuning philosophy I guess .

I can't get new car for this test, I use the same car I use before. Modification that I can't remove is Stage 3 weight mod and rollcage, so I test your car using this modification. When testing I use S3/S3 tire and make my car has the same power and upgrade as yours except the above mentioned.

At mid corner, both car show different handling. While mine just cruise along with no drama, yours need a bit attention on how the car goes. Apply some counter steer when needed. Although your car would tend to drift it's rear, recovering is still easy.

From driver point of view your car is more exciting. I guess by using wheel will make your car a fun car to drive. You can easily control the tail slide by little steer correction. My car looks boring from this point of view.

Braking is also different. Your car have better braking, car stop faster. But I feel both suffer understeer under braking.

I can't compare apply throtle in mid corner handling because I can't do steady cornering in your car.

Using my driving style, your car still a bit hard to handle. I can occasionally do a proper counter steer, but most of the time I make mistake and reduce the speed.

 

[Scaff]

I have tried your car Scaff. It show different tuning philosophy I guess .

I can't get new car for this test, I use the same car I use before. Modification that I can't remove is Stage 3 weight mod and rollcage, so I test your car using this modification. When testing I use S3/S3 tire and make my car has the same power and upgrade as yours except the above mentioned.

At mid corner, both car show different handling. While mine just cruise along with no drama, yours need a bit attention on how the car goes. Apply some counter steer when needed. Although your car would tend to drift it's rear, recovering is still easy.

From driver point of view your car is more exciting. I guess by using wheel will make your car a fun car to drive. You can easily control the tail slide by little steer correction. My car looks boring from this point of view.

Braking is also different. Your car have better braking, car stop faster. But I feel both suffer understeer under braking.

I can't compare apply throtle in mid corner handling because I can't do steady cornering in your car.

Using my driving style, your car still a bit hard to handle. I can occasionally do a proper counter steer, but most of the time I make mistake and reduce the speed.

Thanks for giving it a go, I can't comment on your set-up yet as I did not have a chance to run the car last night, I should (I hope) get the chance tonight.

As far as the understeer goes you will struggle to dial that out of a car of this nature, particularly under braking, that's in part the RR drivetrain for you.

I'm quite happy to admit that I did retain the oversteer on the car, as I have mentioned in the past I personally prefer working with the natural characteristics of the car. As I often find that trying to totally remove them can destroy the joy of driving it.

I wanted to keep the ability to oversteer, but also allow it to be easily controlled, which suits my driving style.

As far as stopping ability goes, you may find that this is the problem...

Brake Controller
-Brakes: 1 / 1

... I would suggest giving my 4/3 settings a go and see if that helps.

Regards

Scaff

 

[sucahyo]

Thanks for giving it a go, I can't comment on your set-up yet as I did not have a chance to run the car last night, I should (I hope) get the chance tonight.

As far as the understeer goes you will struggle to dial that out of a car of this nature, particularly under braking, that's in part the RR drivetrain for you.

Ok.

I'm quite happy to admit that I did retain the oversteer on the car, as I have mentioned in the past I personally prefer working with the natural characteristics of the car. As I often find that trying to totally remove them can destroy the joy of driving it.

I wanted to keep the ability to oversteer, but also allow it to be easily controlled, which suits my driving style.

I thought so .

As far as stopping ability goes, you may find that this is the problem...

... I would suggest giving my 4/3 settings a go and see if that helps.

Yes, thanks, it help .

 

[Scaff]

Suchayo

I've given the car a good run around Apricot Hill with your settings (but with my brake settings - I like to be able to stop LOL).

I have to say I found it quite lacking in front end grip and quite prone to oversteer at times, which could be tricky to keep in check.

I guess my set-up suits me better and I just can't agree with you on running zero camber, still it was interesting to try.

Regards

Scaff

 

[sucahyo]

I see, thanks for testing . Your feed back help me know what it lacks 👍. Maybe I should lower the rear spring rate since I think stiffer spring rate make tire have more grip but also slip easier (increase the chance of slipping).

 

[Scaff]

I see, thanks for testing . Your feed back help me know what it lacks 👍. Maybe I should lower the rear spring rate since I think stiffer spring rate make tire have more grip but also slip easier (increase the chance of slipping).

I think it would certainly be worth a try, but I still believe that you are 'walking' right past settings that may better suit both the car and you.

Rather than just jumping from one extreme to another, try smaller 'step-by-step' increases. So rather than jumping from stabiliser 1/1 straight to 7/1, try working your way up in smaller steps. I know that this does take longer and that you don't always have as much time on GT4 to tune as you would like, but its got to be worth a go.

Regards

Scaff

 

[sucahyo]

The way I tune is usually the same as some (forget the name) search algorithm:
- see if min adequate, if need higher continue test max
- see if max adequate, if need lower continue test half
- see if half adequate, if need lower continue test 1/4, if need higher continue test 3/4.
- ...

Even if I find max value to be adequate I usually check wether using half will give half of what max value give or not. Sometime do reverse to check if it will give the opposite result or not.

For stabilizer I usually need more range than GT4 provide. I tried to tweak the stabilizer yesterday and feel that reducing front stabilizer do not increase front tire grip as much as reducing rear spring rate when the car is driven at the tire limit. When driving bellow tire limit reducing front stabilizer create more oversteer than what I want.

I see that each part tuning has different effect. The way I see it now, tuning will give different effect at:
- during load transfer
- during no load transfer
- at high speed
- at low speed
- at or close to tire limit (tire is almost or already slipping)
- bellow tire limit

Maybe there are other category that we can use to differentiate the effect of each suspension setting.

This is what I use now, I apply some of this when tuning the A310 (may change in the future):
- spring rate have different effect during load transfer vs no load transfer-at tire limit
- ride height have different effect during load transfer vs during no load transfer.
- damper have effect during load transfer
- camber have different effect during load transfer vs during no load transfer.
- toe have different effect during load transfer vs during no load transfer.
- stabilizer have effect during no load transfer-bellow tire limit

 

[cigano]

Sucahyo, here I go again, but you asked for it. Feedback, right?

I looked at the date when you post that set-up. 19th. A coupla days ago.
K, just gonna tear it off quick: you have no idea what springs/dampers do, much less how to use them. There. Again, I don't knoe you, I have nothing against you, this is how I'd say it to some1 at a bar while watching a race on TV.

Now, I suspect it's coz you haven't understood the under/over thing. And that is due to you neglecting to think about weight transfer. And that is coz it apparently hasn't occured to you to think about tires as is their due.

It's all about the tires, dog. That's it. It's those few square inches of rubber surface, and how the forces excerted on them by the car moving make them want to rub against the road.
So from there, what affex the rubbing? Well, the 1 factor most readily to mind is the pressure with which the rubber is pressed against the road. I'll let you name that pressure as the situation dictates.

I however, must continue with the name "weight". Coz the car's very own weight is about the 1 most important thing we can manipulate, in the name of putting pressure that will yield useful grip on the tires.

1 lil aisde: Oversteer is when the front tires are gripping and the rears aren't so much, if at all. Understeer is when the rear is still gripping, but the front lets go for some reason. In either case, the tires that lost the grip battle don't have enuff pressure on them to keep grip against the speed/momentum conditions you have put the car in, and are not doing their job, while the others are. I behoove you to understand this, It is the light that guides all useful tuners....

I don't knoe if you've gotten around to looking at the progress of the Downforce discussion. There I ask about style. Driving and tuning. They go together. You will not drive your best unless you understand what the different parts are doing at any given moment, and how that's helping or hurting - it's never both, a thing either helps or it hurts - your speed. And if you understand what the parts do, and how you're going to use them - what techniques you will apply, when and how hard you brake = style - then tuning them will just explode your speed potential. Just 1 won't do $#!%.

This is all to talk about the real issue in discussing weight: Transfer! Hard, soft, these concepts aren't there for any other reason than to let you think about how to control how the car's MASS moves through the track.
The car is suspended, got it? It's not held fast to the tires. Under forces the car will swwwaaayyyy. Not as much as a bobble-hed doll, but you get my drift.

Now, Sucahyo, you press the gas, the car moves forward. Member the springs? When going anywhere, a thing must overcome inertia. Well, a thing under load from its own weight, and now an accelerating force: if the thing is flexible - like springs mebbe - the point that the pushing force is being directly applied to will move 1st, while the points outside the direct action of the push will? Will? Sway! That's right. I'm gonna post and continue.

 

[cigano]

In a car's case, it's as if we're applying the force at the bottom-most point, would y'all agree? Now, can you see in ya mind what the top of the car is doing? In case ya don't: it sways BACKWARD. The weight SHIFTS its position, backward. As in the Back, the Rear. OOOhhh, ther's tires in the rear! I bet they getting a lot of pressure on them, boy! I wonder what the chances of these tires - under that pressure - slipping are.

So, how bout this. You now knoe that the tires with the most weight on them are the 1s that will grip, while the others may let go. So if you have an oversteer issue, and you knoe that oversteer is when the rears let go 1st....
I don't knoe but I'd think about helping a goodly amount of the car's weight on the rears.

Now, Sucahyo, what kinda springs settings do you think would be conducive to keeping weight on the rear tires? You think it would happen with 4.0 in front, 10.0 rear? Which number will let its end down more?

 

[eg6_dude]

Proper english is a concept that appears to be hard to grasp for you. Also there is probably no need to sound so impolite all the time.

 

[sucahyo]

Sucahyo, here I go again, but you asked for it. Feedback, right?

Ok thanks

K, just gonna tear it off quick: you have no idea what springs/dampers do, much less how to use them.

It means you have different opinion then. The way I do test seem different than yours.
This is how I learn those.
Spring rate and ride height effect on FR car acceleration
Spring rate and ride height effect on FF car acceleration

Comparing damper behaviour after jumping, this is one of the reason why I believe that GT2 and GT4 damper is reversed.

...
1 lil aisde: Oversteer is when the front tires are gripping and the rears aren't so much, if at all. Understeer is when the rear is still gripping, but the front lets go for some reason. In either case, the tires that lost the grip battle don't have enuff pressure on them to keep grip against the speed/momentum conditions you have put the car in, and are not doing their job, while the others are. I behoove you to understand this, It is the light that guides all useful tuners....
...
This is all to talk about the real issue in discussing weight: Transfer! Hard, soft, these concepts aren't there for any other reason than to let you think about how to control how the car's MASS moves through the track.
...
The car is suspended, got it? It's not held fast to the tires. Under forces the car will swwwaaayyyy. Not as much as a bobble-hed doll, but you get my drift.
...
Now, Sucahyo, you press the gas, the car moves forward. Member the springs? When going anywhere, a thing must overcome inertia. Well, a thing under load from its own weight, and now an accelerating force: if the thing is flexible - like springs mebbe - the point that the pushing force is being directly applied to will move 1st, while the points outside the direct action of the push will? Will? Sway! That's right.
....
In a car's case, it's as if we're applying the force at the bottom-most point, would y'all agree? Now, can you see in ya mind what the top of the car is doing? In case ya don't: it sways BACKWARD. The weight SHIFTS its position, backward. As in the Back, the Rear. OOOhhh, ther's tires in the rear! I bet they getting a lot of pressure on them, boy! I wonder what the chances of these tires - under that pressure - slipping are.

ok. Your explanation is clear.

So, how bout this. You now knoe that the tires with the most weight on them are the 1s that will grip, while the others may let go. So if you have an oversteer issue, and you knoe that oversteer is when the rears let go 1st....
I don't knoe but I'd think about helping a goodly amount of the car's weight on the rears.

Now, Sucahyo, what kinda springs settings do you think would be conducive to keeping weight on the rear tires? You think it would happen with 4.0 in front, 10.0 rear? Which number will let its end down more?

In GT4, it will be more understeer, but also increase tail slide.

In other game, softer end may have more grip. Increasing rear spring rate in GT4 do not reduce grip, it increase grip (incorrect behaviour) but also at the same time increase the chance of the tire slipping (correct behaviour). Notice that I differentiate "grip" with "chance of tire slipping", since I believe that both is different.

I don't do this kind of spring rate tuning in other game.

Have you ever try it? Try my car with 10.0 spring rate in front and 4.0 in rear and you know what I mean.

 

[Scaff]

Comparing damper behaviour after jumping, this is one of the reason why I believe that GT2 and GT4 damper is reversed.

Suchayo I feel that I have to add a little more to the background here, as you appear to be being rather 'selective' in the information you link to on this subject (and the following one).

The thread linked to above regards GT2 and tests that are not fully representative of full damper behaviour (dropping a car from a height is not exactly a subtle test), nor is it particularly valid for GT4.

As an entire thread exists on this subject why did you not link to that? Oh well if you don't want to I will.

GT4 Dampers

In GT4, it will be more understeer, but also increase tail slide.

Under what conditions, at what part of the corner, etc. etc.

This is a conversation we have had many, many times before and I have asked that when you describe handling characteristics and behaviour that you provide detail. What you have said above is that the car is both understeering and oversteering, so without context its rather difficult to discuss.

In other game, softer end may have more grip. Increasing rear spring rate in GT4 do not reduce grip, it increase grip (incorrect behaviour) but also at the same time increase the chance of the tire slipping (correct behaviour). Notice that I differentiate "grip" with "chance of tire slipping", since I believe that both is different.

I don't do this kind of spring rate tuning in other game.

Have you ever try it? Try my car with 10.0 spring rate in front and 4.0 in rear and you know what I mean.

Once again threads already exist on this subject and a huge amount of testing has already been done (but more is always welcome), most of which has not shown that GT4 tuning is reversed , unless very extreme values are used, which does have a real world corrolation.

BTW you can't differentiate grip and slip, the two are related, that is unless you are using a definition of grip and slip that are away from the automotive and racing norm.

As you can see from the above as tyre slip increases so does tractive force (grip) up to the point the tyre reaches its limit of slip, then tractive force (grip) reduces.


Regards

Scaff

 

[sucahyo]

Suchayo I feel that I have to add a little more to the background here, as you appear to be being rather 'selective' in the information you link to on this subject (and the following one).

The thread linked to above regards GT2 and tests that are not fully representative of full damper behaviour (dropping a car from a height is not exactly a subtle test), nor is it particularly valid for GT4.

As an entire thread exists on this subject why did you not link to that? Oh well if you don't want to I will.

GT4 Dampers

Ok . I just put the link to GT2 to proof that I do some testing, putting the link above will require a lot of reading before he get the point ..............

Under what conditions, at what part of the corner, etc. etc.

This is a conversation we have had many, many times before and I have asked that when you describe handling characteristics and behaviour that you provide detail. What you have said above is that the car is both understeering and oversteering, so without context its rather difficult to discuss.

Ok, on my GT4 Alpine A310, by applying much stiffer rear spring rate, at corner, driven close to tire limit: understeer when there is no load transfer happen ("grip"), can snap to oversteer when load transfer happen ("chance of tire slipping").

Once again threads already exist on this subject and a huge amount of testing has already been done (but more is always welcome), most of which has not shown that GT4 tuning is reversed , unless very extreme values are used, which does have a real world corrolation.

Thanks for providing link, it will give alternative opinion. I only explain what knowledge that I use to tune my car.

BTW you can't differentiate grip and slip, the two are related, that is unless you are using a definition of grip and slip that are away from the automotive and racing norm.

As you can see from the above as tyre slip increases so does tractive force (grip) up to the point the tyre reaches its limit of slip, then tractive force (grip) reduces.

Is that the same tire or different tire? I think different tire can have different breakaway point(slip%) or different dynamic grip (relative traction %) or different maximum grip provided (100% grip).

Are all tire have the exact same graph in real life?

Are you really certain that if one tire with different compound has increased grip it always has a fix amount of reduced slip?

If you understand what the meaning of this bellow, maybe you can use it to explain why I should not differentiate grip and slip.

(posted somewhere in tire physics discussion in forum.rscnet.org)

A couple of months ago, Alpine posted some pacejka coefficients and other tyre information in the High Gear Racer Physics forum (this thread).

205/45 ZR 16, pressure=2 bars, load=2500 N
--------------------------------------------------------------------------------
??                       2.2 8.3 0.00951
Free radius              0.295
Radius under load        0.287
Contact patch width      0.198 275
Contact patch length     0.0986 50
Vertical stiffness       263000
Vertical force (load)    2500
Long. carc stiffness     200000
Lat. carc stiffness      110000 11000 1.20
Tors. carc stiffness     10000000
Carros(?) carc stiffness 0.36
Long. caou(?) stiffness  105000
Lat. caou(?) stiffness   57193 1650000 8
Long. static friction    1.203 4.4 0.32
Lat. static friction     1.16 1.1 0.30
Rolling effort           1900
--------------------------------------------------------------------------------

255/45 VR 15, 2.2 bars, 4000 N - rear tyre of Alpine V6 turbo
--------------------------------------------------------------------------------
??                       2.2 8.3 0.01096
Free radius              0.309
Radius under load        0.296
Contact patch width      0.211 373
Contact patch length     0.0601 134
Vertical stiffness       365000
Vertical force (load)    4000
Long. carc stiffness     290000
Lat. carc stiffness      110000 11000 1.20
Tors. carc stiffness     20000000
Carros(?) carc stiffness 2.00
Long. caou(?) stiffness  105000
Lat. caou(?) stiffness   73000 210000 0.40
Long. static friction    1.203 4.4 0.32
Lat. static friction     1.36 1.1 0.30
Rolling effort           5000
--------------------------------------------------------------------------------

 

[Scaff]

Ok, on my GT4 Alpine A310, by applying much stiffer rear spring rate, at corner, driven close to tire limit: understeer when there is no load transfer happen ("grip"), can snap to oversteer when load transfer happen ("chance of tire slipping").

Load transfer from and to what part of the car? You can't simply say no load transfer as unless a car is stationary some degree of load transfer is always going to be occuring (unless you are hold an exactly steady throttle and have zero steering input - almost impossiable in the real world).

Is that the same tire or different tire? I think different tire can have different breakaway point(slip%) or different dynamic grip (relative traction %) or different maximum grip provided (100% grip).

Are all tire have the exact same graph in real life?

The graph is quite clearly illustrative, it shows the pattern of traction in relation to slip (angle or percentage or combined), the point of breakaway will vary depending on a huge range of factors (such as load on the tyre, temperature, compound, etc) and will dynamically change as you drive. Each tyre would have its own breakway point as each tyre is operating under different conditions.

In addition varying tyre compounds will have different characteristics, such as how sharply they lose traction after the breakaway point. Racing tyres are a good example of varying traction vs slip curves, when cold they will have a lower slip limit and lose tractive force sharply, but once up to temperature the slip limit will be very high (in comparison to a road legal tyre) and lose tractive force in a much more progressive manner. This will of course vary from manufacturer to manufacturer and tyre to tyre.

Road tyres are much different, designed to be consistent across a wide range of temperatures, but tending to lose tractive force much more rapidly once the slip limit is exceeded.

Are you really certain that if one tire with different compound has increased grip it always has a fix amount of reduced slip?

I did not say that at all!!!!

Please do not start this again, you have been warned before about attemps to put words in people mouths.

If you understand what the meaning of this bellow, maybe you can use it to explain why I should not differentiate grip and slip.
(posted somewhere in tire physics discussion in forum.rscnet.org)

A couple of months ago, Alpine posted some pacejka coefficients and other tyre information in the High Gear Racer Physics forum (this thread).

First off I don't see why the graph I originally used (source - Going Faster - The Skip Barber Race School) is not enough, it quite clearly shows the relationship between the two. I could easily shower you in quotes, graphs and information from a huge range of sources on this. How about this time you simply accept that its true and we move on, rather that the standard 'suchayo disputes the world of physics' thread.

Slip and Grip are directly related, as each type develops slip the grip (tractive force) increases, as each tyres slip limit is reached and exceeded it loses grip (tractive force).

This is then directly related to under and over-steer, if the combined slip angles at the rear of the car are greater than those at the front, then its oversteering. If the combined slip angles at the front are greater than those at the rear its understeering.

The info you posted is simply a collection of tyre data values, mainly radius (unloaded and loaded), contact patch dimensions (static), and various longitudinal and latitudinal stiffness figures, oh and rolling resitance figures. These are some of the figures that can be used to model tyre data for analysis, but in raw form are not of great value.

Regards

Scaff

 

[sucahyo]

Load transfer from and to what part of the car? You can't simply say no load transfer as unless a car is stationary some degree of load transfer is always going to be occuring (unless you are hold an exactly steady throttle and have zero steering input - almost impossiable in the real world).

That is what I mean.

The graph is quite clearly illustrative, it shows the pattern of traction in relation to slip (angle or percentage or combined), the point of breakaway will vary depending on a huge range of factors (such as load on the tyre, temperature, compound, etc) and will dynamically change as you drive. Each tyre would have its own breakway point as each tyre is operating under different conditions.

In addition varying tyre compounds will have different characteristics, such as how sharply they lose traction after the breakaway point. Racing tyres are a good example of varying traction vs slip curves, when cold they will have a lower slip limit and lose tractive force sharply, but once up to temperature the slip limit will be very high (in comparison to a road legal tyre) and lose tractive force in a much more progressive manner. This will of course vary from manufacturer to manufacturer and tyre to tyre.

Road tyres are much different, designed to be consistent across a wide range of temperatures, but tending to lose tractive force much more rapidly once the slip limit is exceeded.

Ok, From this explanation you said that point of breakaway will change dynamically when driving, this is what I refer as slip.

If I use those graph. By increasing GT4 spring rate, the overall grip will increase and point of breakaway will reduce.

I did not say that at all!!!!

Please do not start this again, you have been warned before about attemps to put words in people mouths.

Sorry, I thought that what you mean.

First off I don't see why the graph I originally used (source - Going Faster - The Skip Barber Race School) is not enough, it quite clearly shows the relationship between the two. I could easily shower you in quotes, graphs and information from a huge range of sources on this. How about this time you simply accept that its true and we move on, rather that the standard 'suchayo disputes the world of physics' thread.

Slip and Grip are directly related, as each type develops slip the grip (tractive force) increases, as each tyres slip limit is reached and exceeded it loses grip (tractive force).

This is then directly related to under and over-steer, if the combined slip angles at the rear of the car are greater than those at the front, then its oversteering. If the combined slip angles at the front are greater than those at the rear its understeering.

I see, I use wrong term then. Not "chance of tire slipping" but should be "slip limit".

The info you posted is simply a collection of tyre data values, mainly radius (unloaded and loaded), contact patch dimensions (static), and various longitudinal and latitudinal stiffness figures, oh and rolling resitance figures. These are some of the figures that can be used to model tyre data for analysis, but in raw form are not of great value.

Ok.

 

[Scaff]

That is what I mean.

You still have not answered the question at all. You clearly said "understeer when there is no load transfer happen ", so either you are saying the car is understeering when its stationary (or you have such fine car control that you can balance the car perfectly when driving - this one I seriously doubt). So I ask again the car is understeering and/or oversteering under what conditions? Be clear and detailed in what you describe, because so far its made little or no real sense.

Ok, From this explanation you said that point of breakaway will change dynamically when driving, this is what I refer as slip.

If thats the case how can you even begin to claim that slip and grip are not
related, they quite clearly are.

If I use those graph. By increasing GT4 spring rate, the overall grip will increase and point of breakaway will reduce.

Again this is simply far to simplistic. Which end of the car are you attempting to increase the spring rate at? Which tyre (or tyres) are you trying to say will be effected? Without this context the graph and your statement are meaningless.

In addition you are using just one part of your set-up to try and justify a general statement for all tuning. yet if we look at the set-up itself.

Suspension
-Spring Rate: 4.0 / 10.0
-Ride Height: 180 / 180
-Bound: 10 / 1
-Rebound: 10 / 1
-Camber: 0.0 / 0.0
-Toe: 0 / -4
-Stabilizers: 7 / 1


You are claiming that this proves that a stiff set of springs at the rear are causing more grip, yet ignoring the fact that you have a much softer rear set-up in terms of both Stabilisers and Dampers (again I believe that your dogmatic refusal to look at dampers correctly is part of the problem here). You have the opposite problem at the front end of the car, but thats compounded by a high ride height and soft spring rate increaseing the body roll with no camber set to maximise front end grip.

Now you are trying to take one element of this very conflicted set-up and use it to prove a point across all GT4 tuning, yet yo uadmit yourself that you don't use step by step (incremental) tuning to see how small changes can effect the balance of a car.

I have to say that once again not only do I find you logic flawed, but your entire approach to testing itself flawed.

Sorry

Scaff

 

[sucahyo]

You still have not answered the question at all. You clearly said "understeer when there is no load transfer happen ", so either you are saying the car is understeering when its stationary (or you have such fine car control that you can balance the car perfectly when driving - this one I seriously doubt). So I ask again the car is understeering and/or oversteering under what conditions? Be clear and detailed in what you describe, because so far its made little or no real sense.

"no load trasnfer happen": at about 70mph, push the turn button and throttle button at the same time in a couple of second, watch how the car behave after the first or two second (when there is no more swaying), make sure the car still on the road while you doing this, Apricot Hill has some corner that allow this. For spring rate, increase rear if oversteer, decrease rear if understeer.

If thats the case how can you even begin to claim that slip and grip are not
related, they quite clearly are.

I just notice your previous post:
"BTW you can't differentiate grip and slip, the two are related, that is unless you are using a definition of grip and slip that are away from the automotive and racing norm."

I don't know that in English the word "different" can also mean "not related". Where in my mind I think that wether related or not, grip and slip limit are different. The same way you and I are different or my brother and I are different, where in last case my brother and I are related.

I thought that when you don't agree grip and slip limit is different, you trying to say that grip and slip limit are alike.

Again this is simply far to simplistic. Which end of the car are you attempting to increase the spring rate at? Which tyre (or tyres) are you trying to say will be effected? Without this context the graph and your statement are meaningless.

General. I start learning it at monaro, and then applying it at Audi R8 and this Alpine A310. I already said that I believe increasing spring rate would create more grip and increase the chance of tire slipping. Those graph is a representation of what I think about how spring rate will affect car handling behaviour.

So, if a car, any car, have tendency to loose rear tire grip while load transfer happen, which I suspect caused by high chance of tire slipping (a low value of breakaway point), my action would be to reduce spring rate with a trade off of reduced rear tire grip when no load transfer happen.

If a car, any car, have understeer behavior when no load transfer happen, my action would be to increase rear spring rate if stabilizer can't cure it, with the trade off of increased chance of rear tire slipping.

In addition you are using just one part of your set-up to try and justify a general statement for all tuning. yet if we look at the set-up itself.

...

You are claiming that this proves that a stiff set of springs at the rear are causing more grip, yet ignoring the fact that you have a much softer rear set-up in terms of both Stabilisers and Dampers (again I believe that your dogmatic refusal to look at dampers correctly is part of the problem here). You have the opposite problem at the front end of the car, but thats compounded by a high ride height and soft spring rate increaseing the body roll with no camber set to maximise front end grip.

Now you are trying to take one element of this very conflicted set-up and use it to prove a point across all GT4 tuning, yet yo uadmit yourself that you don't use step by step (incremental) tuning to see how small changes can effect the balance of a car.

About damper, I still waiting for your experiment about damper solution to cure lift off oversteer/understeer problem, this is what I am trying to cure. How do you know that it's incorrect?

About stabilizer, I already explain at my first post that those extreme stabilizer value is still not enough, I still feel plenty of oversteer. And besides, for me, the understeer created by changing stabilizer do not feel the same as the understeer created by changing spring rate. I may use both in a conflicting way in the future.

So you think my car weak front tire grip caused by "compounded by a high ride height and soft spring rate increaseing the body roll with no camber set to maximise front end grip"? try using lowest spring rate value for front and rear fro my car, and see if my car still understeer. I say this tweak will make the rear one weaker, not make the front stronger.

About small change, I still think that small change has small effect and big change has big effect, if the reverse big one show worse effect and the normal big one is not enough why bother using the small one.

 

[Scaff]

"no load trasnfer happen": at about 70mph, push the turn button and throttle button at the same time in a couple of second, watch how the car behave after the first or two second (when there is no more swaying), make sure the car still on the road while you doing this, Apricot Hill has some corner that allow this. For spring rate, increase rear if oversteer, decrease rear if understeer.

Hold on you are trying to say here that no load transfer is occurring when a car is cornering on the throttle?

Care to explain how this is the case, as even in a constant radius cornering situation its almost impossible to keep the throttle and steering at a fixed point, which would be required for no load transfer to occur.

Every steering input, change of throttle or brake position, gear change will cause load to transfer. Some transfers will be smooth and small and some will not, but they are occurring.

I would strongly suggest you re-read the section in my manual or greyouts stickied thread above on how spring rates and load transfer relate to each other, as I do feel that you are missing something here.

I just notice your previous post:
"BTW you can't differentiate grip and slip, the two are related, that is unless you are using a definition of grip and slip that are away from the automotive and racing norm."

I don't know that in English the word "different" can also mean "not related". Where in my mind I think that wether related or not, grip and slip limit are different. The same way you and I are different or my brother and I are different, where in last case my brother and I are related.

I thought that when you don't agree grip and slip limit is different, you trying to say that grip and slip limit are alike.

Which is exactly why I asked the question.

I did not say they were the same, but you did say they were unrelated and as I hope you now agree (because if you're not your arguing with the laws of physics, not just me), that they are firmly linked.

So, if a car, any car, have tendency to loose rear tire grip while load transfer happen, which I suspect caused by high chance of tire slipping (a low value of breakaway point), my action would be to reduce spring rate with a trade off of reduced rear tire grip when no load transfer happen.

If a car, any car, have understeer behavior when no load transfer happen, my action would be to increase rear spring rate if stabilizer can't cure it, with the trade off of increased chance of rear tire slipping.

Once again you are just saying "while load transfer happen", load transfer to where? You have to be more specific about this, you can't just say load transfer and expect it to mean anything.


An example:
A powerful rear wheel drive car can oversteer on throttle application, the load here is transferring to the rear, but the torque is overwhelming the rear tyres and resulting in oversteer.

The same rear wheel drive car is cornering at starting to run wide (understeer), the driver lifts off the throttle which transfers load to the front of the car, unloading the rear tyres and resulting in a shift from understeer to oversteer.

Now both of these situations result in oversteer and both involve load transfer, but in only one of them is the load transfer the cause of the oversteer.

Vehicle dynamics is a complex and often confusing area and I feel that at times you grab hold of a concept and run off into the distance with it, rather that slowing down and looking (and asking) how it works in relation to the other factors involved. I've now seen you do this with dampers, spring rates and camber; a definite pattern exists here, its just a shame that it appears to be only you that can't see it.

About damper, I still waiting for your experiment about damper solution to cure lift off oversteer/understeer problem, this is what I am trying to cure. How do you know that it's incorrect?

Again you expect one solution that will fit every car and every situation, you can't be this general. I have always said that you need to look at all the factors involved in the cause of a problem, before looking at a solution and that solution requires all the factors of tuning to be involved.

That's exactly why my guides don't say if X happens then doing Y will always cure it, because tuning does not work like that. You have general rules of behaviour that are to a degree predictable and you can know which parts of the suspension are active; for example dampers are a significant factor while load is being transferred, but once the load has settled (and this is not the same as no load transfer) they have minimal effect. So as a car enters or exits a corner dampers are a factor, but in a constant radius corner they are a lot less of a factor. That said how these different elements work with each other is often a lot less predictable, the same goes for differing cars, with different drive-trains, static weight distribution, etc.

About small change, I still think that small change has small effect and big change has big effect, if the reverse big one show worse effect and the normal big one is not enough why bother using the small one.

You can think it all you like, many of us have tested this (the entire is suspension tuning backwards thread covers this and I carried out weeks of testing for the manuals in this area), and its simply not correct. The use of extreme values can and does often have unexpected results, going softer will normally increase grip at that end (or rather share the load more equally), but that is not a finite statement, go to far and the tyres contact patch can start to distort from the increased roll and the bump stops may be hit, both of these can result in very unexpected results, often a loss of grip.

It can work something like this

Spring rate
7.0 - Base level
6.0 - grip increase from above (load shared better)
5.0 - grip increase from above (load shared better)
4.0 - grip decrease from above (contact patch starts to distort)
3.0 - grip massively decreases from above (contact patch distorted massively)

Now the above is obviously illustrative and does not exactly represent any specific car, but I (and others) have tested this in GT4 and it does represent what can happen in the real world. So it would be possible to jump straight to a soft setting, the car understeers and you jump to the wrong conclusion.


Regards

Scaff

 

[sucahyo]

Hold on you are trying to say here that no load transfer is occurring when a car is cornering on the throttle?

It happen, momentarily, this is the reason why we wait a couple of second. Waiting the car to settle down, when there is no more swaying or jerking, this is what I mean before as "(when there is no more swaying)". After this I consider the condition to be good enough to test the "no load transfer happen" behaviour. This require me to find corner that allow me to do this.

Care to explain how this is the case, as even in a constant radius cornering situation its almost impossible to keep the throttle and steering at a fixed point, which would be required for no load transfer to occur.

Every steering input, change of throttle or brake position, gear change will cause load to transfer. Some transfers will be smooth and small and some will not, but they are occurring.

I already said it before that when tuning I don't adapt my driving style to the corner, but I utilize corner to test my tuning.

Once again you are just saying "while load transfer happen", load transfer to where? You have to be more specific about this, you can't just say load transfer and expect it to mean anything.

In spesific, while we do turning and braking, turning and lift off throttle, turning and powering on, zigzaging, sudden full lock turning, countersteering etc. Are the any short word that can represent this?

When I do testing about handling, I try to not include powerfull torque in equation.

The same rear wheel drive car is cornering at starting to run wide (understeer), the driver lifts off the throttle which transfers load to the front of the car, unloading the rear tyres and resulting in a shift from understeer to oversteer.

Now both of these situations result in oversteer and both involve load transfer, but in only one of them is the load transfer the cause of the oversteer.

In that case, I don't use spring rate to cure it, I use damper. In GPL I would use differential too, but in GT4 I still learning.

Vehicle dynamics is a complex and often confusing area and I feel that at times you grab hold of a concept and run off into the distance with it, rather that slowing down and looking (and asking) how it works in relation to the other factors involved. I've now seen you do this with dampers, spring rates and camber; a definite pattern exists here, its just a shame that it appears to be only you that can't see it.

By understanding how the taste of each suspension part, I hope to make a better car. If my tuning feel to sour or too sweet, from the feedback I can already guess what I need to do.

I do mistakes initially, but now I am satisfied with the result of my tuned car. If it work for me, I don't see the reason not to use it, no matter how bizzare my knowledge is in real life. But still I 'll be carefull of what I should suggest to my father .

Again you expect one solution that will fit every car and every situation, you can't be this general. I have always said that you need to look at all the factors involved in the cause of a problem, before looking at a solution and that solution requires all the factors of tuning to be involved.

Is this why you don't do the experiment yet? I have been using damper to cure lift off/power on creating understeer/oversteer starting from Ford GT '05 until now and still satisfied with how effective it is.

That's exactly why my guides don't say if X happens then doing Y will always cure it, because tuning does not work like that. You have general rules of behaviour that are to a degree predictable and you can know which parts of the suspension are active; for example dampers are a significant factor while load is being transferred, but once the load has settled (and this is not the same as no load transfer) they have minimal effect. So as a car enters or exits a corner dampers are a factor, but in a constant radius corner they are a lot less of a factor. That said how these different elements work with each other is often a lot less predictable, the same goes for differing cars, with different drive-trains, static weight distribution, etc.

Instead of taking the complicated path and trying to solve it all at once, I took the simple step by step way.

Instead of doing multiple tweak at once, I do it one part at a time. When I change one part of suspension, I don't make a difficult guessing on what to be done to the other suspension part in order keep the balance. I will detect what is wrong with the car, and choose what appropriate part that would do best to cure it. If someone find weakness in my car, it is usually caused by my mistakes of doing wrong diagnosis not by using the wrong cure.

You can think it all you like, many of us have tested this (the entire is suspension tuning backwards thread covers this and I carried out weeks of testing for the manuals in this area), and its simply not correct. The use of extreme values can and does often have unexpected results, going softer will normally increase grip at that end (or rather share the load more equally), but that is not a finite statement, go to far and the tyres contact patch can start to distort from the increased roll and the bump stops may be hit, both of these can result in very unexpected results, often a loss of grip.

It can work something like this

Spring rate
7.0 - Base level
6.0 - grip increase from above (load shared better)
5.0 - grip increase from above (load shared better)
4.0 - grip decrease from above (contact patch starts to distort)
3.0 - grip massively decreases from above (contact patch distorted massively)

Now the above is obviously illustrative and does not exactly represent any specific car, but I (and others) have tested this in GT4 and it does represent what can happen in the real world. So it would be possible to jump straight to a soft setting, the car understeers and you jump to the wrong conclusion.

I already explain the algorithm that I use, and it involved testing min max and middle. If I miss the anomaly between, I take that risk. This is the environment I grew up with (in computer science), missing the maximum value but getting the optimal is considered to be ok. Besides, it's the final result that count. And I satisfied with it. I may do major rethinking if some one find my tuned car to be ugly, but so far I don't see the reason yet.


If you want to make your Alpine A310 as understeer as mine, what will you do? What plan or what suggestion?

 

[Scaff]

It happen, momentarily, this is the reason why we wait a couple of second. Waiting the car to settle down, when there is no more swaying or jerking, this is what I mean before as "(when there is no more swaying)". After this I consider the condition to be good enough to test the "no load transfer happen" behaviour. This require me to find corner that allow me to do this.

I think this is a case of 'lost in translation'. You are saying 'no load transfer occurs', which is saying (to me) that no load has moved at all, now unless the car is stationary that's just not possible. From the greater detail you have given above I think what you are trying to say is 'after the load has transferred', which is something quite different indeed.

It still doesn't answer my question of what the 'exact' situation you are describing is. Are you entering a corner? Exiting? Has the load transferred to the front, rear or side of the car (or a combination)?

I already said it before that when tuning I don't adapt my driving style to the corner, but I utilize corner to test my tuning.

This has absolutely nothing to do with driving style at all, but you inability or unwillingness to describe the circumstances of what is happening with the car.

In spesific, while we do turning and braking, turning and lift off throttle, turning and powering on, zigzaging, sudden full lock turning, countersteering etc. Are the any short word that can represent this?

Not that are going to make this easier to discuss. You need to be clear in what is occurring, I do my best to (as do most people here) but you seem to think is OK just to say a car is understeering or that load is transferring and without context these statements are useless.

When I do testing about handling, I try to not include powerfull torque in equation.

Really, care to explain how you tuned the Ford GT and managed to avoid torque getting in the way?

Is this why you don't do the experiment yet? I have been using damper to cure lift off/power on creating understeer/oversteer starting from Ford GT '05 until now and still satisfied with how effective it is.

I havent done the testing yet as I have been very busy both at work and home, but when I have a clear few hours I will do them. However as I have said no one cure fits all situations.

I would also have to disagree as to the effectiveness of your method, yes it may reduce lift-off oversteer, but normally by producing a massive increase in understeer, which is hardly conducive to a well balanced car.

Instead of doing multiple tweak at once, I do it one part at a time. When I change one part of suspension, I don't make a difficult guessing on what to be done to the other suspension part in order keep the balance. I will detect what is wrong with the car, and choose what appropriate part that would do best to cure it. If someone find weakness in my car, it is usually caused by my mistakes of doing wrong diagnosis not by using the wrong cure.

I haven't suggested that you (or anyone) should carry out multiple tweaks, in fact I recommend the exact opposite when tuning.

What I said was that you need to be aware of the other settings when you tune, you can change a spring rate without thinking about the ride height, damper settings, stabilisers, toe, etc. You on the other hand has told people i the past to just look at certain settings and that the rest don't matter, which is both patently rubbish and very bad advice.

I also totally disagree in regard to your point on the diagnosis vs. cure, I've seen you make errors in both.

I already explain the algorithm that I use, and it involved testing min max and middle. If I miss the anomaly between, I take that risk. This is the environment I grew up with (in computer science), missing the maximum value but getting the optimal is considered to be ok. Besides, it's the final result that count. And I satisfied with it. I may do major rethinking if some one find my tuned car to be ugly, but so far I don't see the reason yet.

You are not missing the 'anomaly between', you are selecting the anomaly, nor can you say you are getting the optimal value as you have not tested to see.

This is quite frankly a poor testing method in my opinion (it may work fine in computer science but this is suspension set-up), not only that but yo are reaching flawed conclusions as a result and that's just poor methodology.

I have not problem with you saying that setting maximum softness on spring rates can cause understeer, in fact I said much the same thing in my tuning guides. That is however a long way from saying that softening spring rate causes understeer or that spring rates work the wrong way around, that would require extensive testing of incremental spring rates (say by 0.2 increases and decreases), which is exactly what I did over a wide range of cars and drivelines.

Not only that but you ignore all other suspension values when you discuss this, trying to look at in isolation, when in truth you have often set very extreme values in these areas as well, yet you seemingly dismiss any factor they may play.

If you want to make your Alpine A310 as understeer as mine, what will you do? What plan or what suggestion?

First off why would I want to make it understeer like yours?

Second would be once again to ask for clarification, understeer under what circumstances? I mean if we are talking increasing understeer on corner entry I don't need to change the suspension at all, just carry too much speed and turn-in, massive understeer occurs.

Could you please explain exactly what you are asking here.


Regards

Scaff

 

[sucahyo]

I think this is a case of 'lost in translation'. You are saying 'no load transfer occurs', which is saying (to me) that no load has moved at all, now unless the car is stationary that's just not possible. From the greater detail you have given above I think what you are trying to say is 'after the load has transferred', which is something quite different indeed.

I don't see the difference, I thiking that after the load has transferred, there would be no load transfer occurs.

It still doesn't answer my question of what the 'exact' situation you are describing is. Are you entering a corner? Exiting? Has the load transferred to the front, rear or side of the car (or a combination)?

I can't categorized load transfer tuning like that because it really depend on your driving style. One person may use constant counter steering when in mid corner, while other still applying brake, other use constant steering while doing throttle control, other just start using throttle. With varying way of taking corner, I can't describe it as which corner taking stage it is. If I describe it with how I taking corner, people just see how I take the corner not the way I tune it.

This has absolutely nothing to do with driving style at all, but you inability or unwillingness to describe the circumstances of what is happening with the car.

I am the one who create circumtances for the car, not the corner. I specifically make the car to have spesific conditioning. While this probably not happen while attempting to get fast lap time, this greatly help me decide what is wrong with the car.

Not that are going to make this easier to discuss. You need to be clear in what is occurring, I do my best to (as do most people here) but you seem to think is OK just to say a car is understeering or that load is transferring and without context these statements are useless.2

You said it your self that load transfer can happen on any cornering stage. And it is not "what is occurring" but "what I want to occur".

Really, care to explain how you tuned the Ford GT and managed to avoid torque getting in the way?

By making observation when the rear wheel do not spin.

I havent done the testing yet as I have been very busy both at work and home, but when I have a clear few hours I will do them.

Ok.

However as I have said no one cure fits all situations.

It's not the only solution, but damper cure those problem best for me. I can't think situation where damper can't be used to cure problem which happen when load transfer occur.

I would also have to disagree as to the effectiveness of your method, yes it may reduce lift-off oversteer, but normally by producing a massive increase in understeer, which is hardly conducive to a well balanced car.

How do you know? you don't test it yet. If you use FC suspension, you have the option to separate between bound and rebound. And since damper has very little effect "after load transfer happen" this will not change the overall balance. If you want to cure only lift off oversteer, use front damper bound and rear damper rebound, this should not interfere with apply throttle handling.

I haven't suggested that you (or anyone) should carry out multiple tweaks, in fact I recommend the exact opposite when tuning.

What I said was that you need to be aware of the other settings when you tune, you can change a spring rate without thinking about the ride height, damper settings, stabilisers, toe, etc. You on the other hand has told people i the past to just look at certain settings and that the rest don't matter, which is both patently rubbish and very bad advice.

I also totally disagree in regard to your point on the diagnosis vs. cure, I've seen you make errors in both.

I improve, but still thinking that each part in suspension has different taste. It is possible to use one suspension part and still retain the taste of other suspension setting. For damper the taste is it has effect when there is load transfer happen. It won't change much of the feel of current handling "after load transfer happen".

I am saying that for some spesific problem there is suspension part that can cure it best, unrelated to what the value of other suspension setting.

Like what I usually use to cure "after load transfer happen" understeer. I usually use stabilizer, which I think the best option to cure it. When I change stabilizer, I think that no matter what your other suspension value curently have, lowering front stabilizer will always result to more oversteer. Spring rate or ride height wouldn't prevent that from happening no matter what value those two current value has. Maybe camber make tuning more unpredictable, but it still do not prevent us from making the car more oversteer if we use it at maximum degree.

You are not missing the 'anomaly between', you are selecting the anomaly, nor can you say you are getting the optimal value as you have not tested to see.

This is quite frankly a poor testing method in my opinion (it may work fine in computer science but this is suspension set-up), not only that but yo are reaching flawed conclusions as a result and that's just poor methodology.

I have not problem with you saying that setting maximum softness on spring rates can cause understeer, in fact I said much the same thing in my tuning guides. That is however a long way from saying that softening spring rate causes understeer or that spring rates work the wrong way around, that would require extensive testing of incremental spring rates (say by 0.2 increases and decreases), which is exactly what I did over a wide range of cars and drivelines.

Not only that but you ignore all other suspension values when you discuss this, trying to look at in isolation, when in truth you have often set very extreme values in these areas as well, yet you seemingly dismiss any factor they may play.

Funny thing is, I satisfied using this kind of tuning . I already explain that I feel the range of GT4 suspension is not enough, so I do not feel bad using extreme value.

I satisfied with my methodology, I tell everyone about it. It's up to anyone to decide wether my methodology is usefull or garbage. Anyone can just drive my car, compare it with his/her own car or stock car, and tell it straight to me wether my car is garbage or not. They can post it openly too, just as long as anyone use my car setting that created after Ford GT '05.

Do my car handle worse than car with no suspension upgrade? Do my Alpine A310 has horrible behaviour? I want to know your opinion.

First off why would I want to make it understeer like yours?

I want to know how you tune. I want to know how you make your car handle like mine with your own way, without actually testing. I want to know what do you intend to do. But nevermind, forget it.

 

[Scaff]

I don't see the difference, I thiking that after the load has transferred, there would be no load transfer occurs.

I can't categorized load transfer tuning like that because it really depend on your driving style. One person may use constant counter steering when in mid corner, while other still applying brake, other use constant steering while doing throttle control, other just start using throttle. With varying way of taking corner, I can't describe it as which corner taking stage it is. If I describe it with how I taking corner, people just see how I take the corner not the way I tune it.

I am the one who create circumtances for the car, not the corner. I specifically make the car to have spesific conditioning. While this probably not happen while attempting to get fast lap time, this greatly help me decide what is wrong with the car.

You said it your self that load transfer can happen on any cornering stage. And it is not "what is occurring" but "what I want to occur".

This quite simple and I fail to see what the problem you are having is.

You are asking me to comment of how/why I think your car is reacting and I am asking for some clarification on the exact circumstances its occurring under. You can't just say that a car understeers or that something happens when load is transfering, it simply does not provide enough information for anyone to try and recreate the situation.

I've even given you examples of how this can be done, so I ask again, please give a descent description to the cars behaviour and to help out here is an example.

Good explanation - A
As I turn in and lift off the throttle, load transfers to the front, this results in oversteer as the front grips and the rear end steps out when they lose traction.

Bad explanation - A
Car oversteers when load transfers


Good explanation - B
Turning into the corner on a constant throttle, even with the load already transferred and settled the front tyres lack grip and the car understeers.

Bad explanation - B
Car undesteers when no load transfers


Now I hope the above clearly illustrates the point, I'm not asking for you to write a book, simply to give people enough information to work with.

By making observation when the rear wheel do not spin.

Sucahyo you seem to have forgotten that I have driven most of the cars you are talking about (in fact the only one I can think I have not yet driven is the Monaro) and your Ford GT set-up most certainly did allow the rear tyres to spin.

Even if you control it using the throttle, you are still having to deal with it. I do however have to ask did you find that your damper settings helped reduce wheel spin on the Ford GT?

It's not the only solution, but damper cure those problem best for me. I can't think situation where damper can't be used to cure problem which happen when load transfer occur.

I don't believe I said different, what I said was that its not the only factor involved and that I believe your 'solution' causes other problems. That however is not surprising as almost every aspect of tuning solving one problem leads to another popping up. Its always a compromise.

How do you know? you don't test it yet. If you use FC suspension, you have the option to separate between bound and rebound. And since damper has very little effect "after load transfer happen" this will not change the overall balance. If you want to cure only lift off oversteer, use front damper bound and rear damper rebound, this should not interfere with apply throttle handling.

Just because I have not carried out your specific tests yet does not mean I have not carried out work in this area at all. You seem to forget that I have been tuning in GT for quite a while now, the amount of work that went into the guides alone gives me a degree of understanding here. In addition you seem to be talking about lift-off oversteer as if its always a bad thing, quite the opposite in certain cars its a blessing.

In regard to your last point I would like you to explain exactly why you believe that "use front damper bound and rear damper rebound, this should not interfere with apply throttle handling", don't mess around and try and pass the question back, simply answer the question.

I improve, but still thinking that each part in suspension has different taste. It is possible to use one suspension part and still retain the taste of other suspension setting. For damper the taste is it has effect when there is load transfer happen. It won't change much of the feel of current handling "after load transfer happen".

You are aware that you have just contradicted yourself here.

I totally agree that you still get effects from the rest of the set-up when you tune one area, thats because they are related and will effect each other. Its exactly what I have been saying.

I am saying that for some spesific problem there is suspension part that can cure it best, unrelated to what the value of other suspension setting.

Like what I usually use to cure "after load transfer happen" understeer. I usually use stabilizer, which I think the best option to cure it. When I change stabilizer, I think that no matter what your other suspension value curently have, lowering front stabilizer will always result to more oversteer. Spring rate or ride height wouldn't prevent that from happening no matter what value those two current value has. Maybe camber make tuning more unpredictable, but it still do not prevent us from making the car more oversteer if we use it at maximum degree.

The first part here you contradict what you have said in the last quote.


As far as teh second part goes, go back and read what I have said and read the guides again. The effect and influence each other, yes lowering the front stabiliser value will increase oversteer, but its still going to be effected by the other settings. They will influence how much it increases the oversteer by.

Funny thing is, I satisfied using this kind of tuning . I already explain that I feel the range of GT4 suspension is not enough, so I do not feel bad using extreme value.

I satisfied with my methodology, I tell everyone about it. It's up to anyone to decide wether my methodology is usefull or garbage. Anyone can just drive my car, compare it with his/her own car or stock car, and tell it straight to me wether my car is garbage or not. They can post it openly too, just as long as anyone use my car setting that created after Ford GT '05.

They can tell you but you will not listen, you have not listen to a damn thing that has been said to you in the vast majority of threads here, that's my single biggest issue.

Do my car handle worse than car with no suspension upgrade? Do my Alpine A310 has horrible behaviour? I want to know your opinion.

I have to say that yes (from memory) I do prefer the Alpine with no suspension upgrade. I found your car to be almost totally lacking in front end-grip, mainly a product of the extreme front stabiliser and damper settings (both far to still) which slow down the suspension reaction, it still moves quite a bit as a result of the low spring rate, but this simply compounds the problem as you have no front camber set to compensate for this.

I want to know how you tune. I want to know how you make your car handle like mine with your own way, without actually testing. I want to know what do you intend to do. But nevermind, forget it.

Hold on one minute here I asked a very simple and clear question as I needed some clarification on exactly what you were asking me to do, and you have got funny about it.

Was the part I have highlighted in bold above really needed?

You see I still don't understand why you are asking the question? If I wanted to make a car handle like your I would set it up like yours, do you not see why this question makes no sense.

If you want a car to understeer in almost all circumstances then set the front end up stiff and the rear soft, given that the car in question is a RR layout which will tend to give it a natural understeer bias, with a switch to oversteer if you throw the load forward quickly. However that's a very general summary, as RR tuning gets quite complex you can do a lot to play around with that. For me one of those things is not to try and cure lift off oversteer simply by making the car understeer when load is shifted forward (which is your 'solution').

I'm away with work for a few days now, but I hope to get soem time to play around with this when I get back.

Regards

Scaff

 

[sucahyo]

Now I hope the above clearly illustrates the point, I'm not asking for you to write a book, simply to give people enough information to work with.

Ok. I will explain it like that next.

Sucahyo you seem to have forgotten that I have driven most of the cars you are talking about (in fact the only one I can think I have not yet driven is the Monaro) and your Ford GT set-up most certainly did allow the rear tyres to spin.

Even if you control it using the throttle, you are still having to deal with it. I do however have to ask did you find that your damper settings helped reduce wheel spin on the Ford GT?

Yes, it spin, I test it when it don't spin, I don't test it when it spin. I only observe the car behaviour when the rear tire no longer spinning.

I don't use damper to reduce wheelspin.

I don't believe I said different, what I said was that its not the only factor involved and that I believe your 'solution' causes other problems. That however is not surprising as almost every aspect of tuning solving one problem leads to another popping up. Its always a compromise.

Agree, and when tuning I take the risk of receiving more problem created by my "solution" where I cure this new problem by other "solution".

Just because I have not carried out your specific tests yet does not mean I have not carried out work in this area at all. You seem to forget that I have been tuning in GT for quite a while now, the amount of work that went into the guides alone gives me a degree of understanding here.

Your damper guide seem to mostly mention the relation of damper with bouncy or unstable ride. This (your first guide, page 23):
"The final thing would be then, if required/desired, to adjust the front or rear settings for under or oversteer. I personally always keep the ratio between bound and rebound the same at this point. For example if I was stiffening the rear from 5/6 bound and rebound, by one ‘click’. The final setting would be 6/7 bound and rebound."

not explain it enough. And do not differentiate between lift off throttle and apply throttle behaviour. Using your guide if I want to cure just apply throttle understeer I end up making the lift off throttle behaviour more oversteer too.

I currently use damper tuning just to change the car behaviour related to oversteer and understeer. I don't use it to cure bouncy and unstable behaviour anymore.

If you can, please show me the link to your post where you do the test like this. If not I'll wait for your test.

BTW, I forget that sukerkin already done some experiment with damper related to understeer and oversteer. I find this comment relevant:

"My guess would be that the game, incorrectly, uses the ratio between the Front and Rear Rebounds to create understeer or oversteer. Swap Front and Rear values and see.

...

The bottom line seems to be that for exit oversteer you need a high Front Rebound and a low Rear Rebound. If you want exit understeer (or a sense of 'pointability') then use a low Front Bound and a high Rear Bound. For just a feel of better stability out of corners tho', just a click higher on the Rear Bound seems to help.

Different from my test but it's interesting that he suspect some swapping behaviour in GT4 damper.

In addition you seem to be talking about lift-off oversteer as if its always a bad thing, quite the opposite in certain cars its a blessing.

If it's not a problem, we don't cure it.

In regard to your last point I would like you to explain exactly why you believe that "use front damper bound and rear damper rebound, this should not interfere with apply throttle handling", don't mess around and try and pass the question back, simply answer the question.

Condition:
An FR car in the middle of long corner, currently driving with steady speed, constant steering. car in stable conditon, weight leaning outside.

Case 1. Suddenly you release the throttle, the car will dive, sending weight to the front. Most likely the outside front suspension will compress and the inside rear suspension will expand. When the front suspension compress, the damper value involved is front damper bound value. When the rear suspension expand, the damper value involved is rear rebound value. During this moment the front bound damper, front spring rate, rear rebound damper and rear spring rate will try to resist the diving. By tweaking the value of front bound damper and rear rebound damper we can adjust the behaviour of the car during this occasion.

In my experience, more front bound or less rear rebound make the car more oversteer at lift off throttle.


Case 2. Suddenly you floor the throttle, the car will squat?, sending weight to the rear. Most likely the outside front suspension will expand and the inside rear suspension will compress. When the front suspension expand, the damper value involved is front damper rebound value. When the rear suspension compress, the damper value involved is rear bound value. During this moment the front rebound damper, front spring rate, rear bound damper and rear spring rate will try to resist the squat?. By tweaking the value of front rebound damper and rear bound damper we can adjust the behaviour of the car during this occasion.

In my experience, more front rebound or less rear bound make the car more oversteer at apply throttle.

You are aware that you have just contradicted yourself here.

I totally agree that you still get effects from the rest of the set-up when you tune one area, thats because they are related and will effect each other. Its exactly what I have been saying.

The first part here you contradict what you have said in the last quote.

As far as teh second part goes, go back and read what I have said and read the guides again. The effect and influence each other, yes lowering the front stabiliser value will increase oversteer, but its still going to be effected by the other settings. They will influence how much it increases the oversteer by.

Sound conflicting? I try again.
"It is possible to use one suspension part and still retain the taste of other suspension setting."
"I am saying that for some spesific problem there is suspension part that can cure it best, unrelated to what the value of other suspension setting."

"still thinking that each part in suspension has different taste"

I believe that they will influence each other in a different way not in a uniform way. ie. changing spring rate will not give the same oversteer behaviour as changing stabilizer.

They can tell you but you will not listen, you have not listen to a damn thing that has been said to you in the vast majority of threads here, that's my single biggest issue.

I have different opinion.

I have to say that yes (from memory) I do prefer the Alpine with no suspension upgrade. I found your car to be almost totally lacking in front end-grip, mainly a product of the extreme front stabiliser and damper settings (both far to still) which slow down the suspension reaction, it still moves quite a bit as a result of the low spring rate, but this simply compounds the problem as you have no front camber set to compensate for this.

I see. I tune it to make it easier for me to control the car. In no suspension upgrade condition, I have to struggle to safely pass the corner. So my tuning effort is to make the car more stable passing the corner, reduce the need to use counter steer and reduce the need to do throttle control.

This kind of tuning seem to result in worse handling for you. If I have to tune it for you I think I will reduce front spring rate and change the stabilizer.

You know what this teach me? oversteer problem for me is not really a problem for you. But I still don't know why people describe this car as difficult to drive since you find it easy.

Hold on one minute here I asked a very simple and clear question as I needed some clarification on exactly what you were asking me to do, and you have got funny about it.

Was the part I have highlighted in bold above really needed?

The "forget it" part is not needed. But you missunderstood other part.

"make your car handle like mine":
In your way of tuning, you always advising not to use extreme value. So, I want to know your solution to make your car handle like mine without using extreme value. Use your car as base, use my car as goal.

"what do you intend to do":
I want you to give suggestion, idea, advise of what need to be done without you actually testing it for real. Plan of what you will do, thing that you want to change, not what you feel you must do after you test drive it.


And then after you formulate the recipee for it we can then see how it will turn out.

If you want a car to understeer in almost all circumstances then set the front end up stiff and the rear soft, given that the car in question is a RR layout which will tend to give it a natural understeer bias, with a switch to oversteer if you throw the load forward quickly. However that's a very general summary, as RR tuning gets quite complex you can do a lot to play around with that.

I want to know your plan before you actually playing around with it. Asumming you would use that kind of tuning to make your car drive like mine, from your current setting, which suspension part that you will change. In what priority.

For me one of those things is not to try and cure lift off oversteer simply by making the car understeer when load is shifted forward (which is your 'solution').

I use this damper value for Alpine:
-Bound: 10 / x
-Rebound: x / 1

not to cure lift off oversteer but to cure lift off understeer. I want it to have more lift off overster.

I'm away with work for a few days now, but I hope to get soem time to play around with this when I get back.

That's ok, you don't need to test it right away, just give plan of what you will do with your car, since the plan is what I ask. You can then test it after you get home.

 

[Scaff]

Yes, it spin, I test it when it don't spin, I don't test it when it spin. I only observe the car behaviour when the rear tire no longer spinning.

Why do you only observe the cars behaviour when the tyres are not spinning? If I exit a corner with a bit too much throttle and spin the rear tyres do you not think this should be considered in the tuning?

I don't use damper to reduce wheelspin.

I did not ask if you used the damper to reduce wheelspin, I asked if you found any change to the wheelspin after you tuned the dampers.

Your damper guide seem to mostly mention the relation of damper with bouncy or unstable ride. This (your first guide, page 23):
"The final thing would be then, if required/desired, to adjust the front or rear settings for under or oversteer. I personally always keep the ratio between bound and rebound the same at this point. For example if I was stiffening the rear from 5/6 bound and rebound, by one ‘click’. The final setting would be 6/7 bound and rebound."

not explain it enough. And do not differentiate between lift off throttle and apply throttle behaviour. Using your guide if I want to cure just apply throttle understeer I end up making the lift off throttle behaviour more oversteer too.

I currently use damper tuning just to change the car behaviour related to oversteer and understeer. I don't use it to cure bouncy and unstable behaviour anymore.

If you can, please show me the link to your post where you do the test like this. If not I'll wait for your test.

My tuning guide does quite clearly show the effect of damper values on under and oversteer in general terms, and the example of a tune also discusses this. Quite simply I don't believe or want to force tuning methods on people. The guides (as I say in them) are a starting point to work with, no two cars or drivers will respond to tuning in exactly the same way. You think that dampers are the best/only way to control lift off under/over steer and I disagree, I think that we have many more tools available to us. It for this reason that I don't say that tuning in a set manner will always have a set effect, the dynamics of what is occurring is simply too interlinked to say that setting X must always be used.

For example you have again changed approach in how you use dampers, saying that you no longer use them to control the cars ride, "I don't use it to cure bouncy and unstable behaviour anymore", well I have to ask why? Dampers are one of the main tools to use in this area and now you have done a complete reverse and say that you don't think they need to be used?

BTW, I forget that sukerkin already done some experiment with damper related to understeer and oversteer. I find this comment relevant:


Different from my test but it's interesting that he suspect some swapping behaviour in GT4 damper.

Did you actually read (and fully understand) that thread?

You have taken the swapping comment out of all context, Sukerkin quite clearly says ion the thread that damper values are not reversed and that while some cars will exhibit unusual behaviour in controlling lift off under and over steer, this normally only occurs when the other suspension settings have not been looked at.

As I have always maintained the settings need to be looked at as a whole, and its exactly this conclusion that Sukerkin's thread reaches.

Condition:
An FR car in the middle of long corner, currently driving with steady speed, constant steering. car in stable conditon, weight leaning outside.

Case 1. Suddenly you release the throttle, the car will dive, sending weight to the front. Most likely the outside front suspension will compress and the inside rear suspension will expand. When the front suspension compress, the damper value involved is front damper bound value. When the rear suspension expand, the damper value involved is rear rebound value. During this moment the front bound damper, front spring rate, rear rebound damper and rear spring rate will try to resist the diving. By tweaking the value of front bound damper and rear rebound damper we can adjust the behaviour of the car during this occasion.

In my experience, more front bound or less rear rebound make the car more oversteer at lift off throttle.


Case 2. Suddenly you floor the throttle, the car will squat?, sending weight to the rear. Most likely the outside front suspension will expand and the inside rear suspension will compress. When the front suspension expand, the damper value involved is front damper rebound value. When the rear suspension compress, the damper value involved is rear bound value. During this moment the front rebound damper, front spring rate, rear bound damper and rear spring rate will try to resist the squat?. By tweaking the value of front rebound damper and rear bound damper we can adjust the behaviour of the car during this occasion.

In my experience, more front rebound or less rear bound make the car more oversteer at apply throttle.

Thank you for the expansion, because you have just helped to confirm what I have been maintaining.

You describe the transfer of load during cornering when a car is decelerating and accelerating, now one small correction first, this is not simply dive and squat occuring here, its also roll. As such in addition to the dampers having an effect in the balance and dynamics of the car, spring rates and stabilisers (why do you think they are called anti-roll bars) have a major part to play.

I simply fail to see how you can say that they are not a factor in this, when you have just described the load transfer and it quite clearly indicates that they are a factor. In the real world its common (and I've used it in GT4) to use a soft front stabiliser and stiff rear stabiliser to increase a cars tendency towards lift off oversteer. Its common in FWD race cars, if you have LFS take a look at the default track set-up for the FWD cars, they all run a soft front and stiff rear anti-roll bar.

Example 1 - BTCC Honda Integra Type R

Example 2 - BTCC Nissan Primera

Example 3 - BESTuners Renaultsport Clio 2.0 16v

All three of these were tuned using a combination of springs, dampers and stabilisers to deliberately have a balance towards lift-off oversteer, so please stop implying that I have not worked on or tested in this area.

Sound conflicting? I try again.
"It is possible to use one suspension part and still retain the taste of other suspension setting."
"I am saying that for some spesific problem there is suspension part that can cure it best, unrelated to what the value of other suspension setting."

"still thinking that each part in suspension has different taste"

I believe that they will influence each other in a different way not in a uniform way. ie. changing spring rate will not give the same oversteer behaviour as changing stabilizer.

It may not give exactly the same type of behaviour, but that does not mean that they can be ignored, its naive to try and say so. Real world and GT4 testing proves both to be incorrect.

I see. I tune it to make it easier for me to control the car. In no suspension upgrade condition, I have to struggle to safely pass the corner. So my tuning effort is to make the car more stable passing the corner, reduce the need to use counter steer and reduce the need to do throttle control.

This kind of tuning seem to result in worse handling for you. If I have to tune it for you I think I will reduce front spring rate and change the stabilizer.

You know what this teach me? oversteer problem for me is not really a problem for you. But I still don't know why people describe this car as difficult to drive since you find it easy.

I did not say that I found the car easy to drive with the stock suspension, I said I preferred it to your set-up. I prefer my set-up to both, which should be no surprise.

You have reduced oversteer in your set-up, but in my opinion you have gone to far, the car is now an understeering brick. Yes its easier to drive, but its certainly not as fast as it could be, in fact in your next quote you admit to having gone to far in that you say the car now has too much lift off understeer.

As far as making it better for me by reducing the front spring rate more, I've already described how I feel thats part of the problem, as combined with the lack of camber at the front its not going to increase grip but reduce it.

"make your car handle like mine":
In your way of tuning, you always advising not to use extreme value. So, I want to know your solution to make your car handle like mine without using extreme value. Use your car as base, use my car as goal.

Your car handles as it does because of your settings.

The two points already exist, my car and your car. To make my car handle the same as your I would have to set it up as yours is.

"what do you intend to do":
I want you to give suggestion, idea, advise of what need to be done without you actually testing it for real. Plan of what you will do, thing that you want to change, not what you feel you must do after you test drive it.

I want to know your plan before you actually playing around with it. Asumming you would use that kind of tuning to make your car drive like mine, from your current setting, which suspension part that you will change. In what priority.

I use this damper value for Alpine:
-Bound: 10 / x
-Rebound: x / 1

not to cure lift off oversteer but to cure lift off understeer. I want it to have more lift off overster.

That's ok, you don't need to test it right away, just give plan of what you will do with your car, since the plan is what I ask. You can then test it after you get home.

For the sake of closing this one down, I have already given you an idea of how I would generally aproach a balance that you have achieved, so why are you asking me for a 'plan' again.

I repeat

If you want a car to understeer in almost all circumstances then set the front end up stiff and the rear soft, given that the car in question is a RR layout which will tend to give it a natural understeer bias, with a switch to oversteer if you throw the load forward quickly.

I don't plan out tuning any more than that before driving the car (in point of fact had I not already driven the car I would not have even given you that), how can I get this through to you. I do not tune in this way, you may like deciding exactly how to tune a car in advance and then sticking to that plan, I do not. Nor will I, I find it a flawed approach to take, it limits the tuner and for me tuning is a process that evolves when you carry it out.

Regards

Scaff

 

[Leonidae]

I see that you two have got bit carried away. anyways, it seems that you two have way too much fun, so I think that I'll say something here as well..

This is my teachers suspension tuning guide, that he has created on multiple racetracs while adjusting Super2000-class Integra Type R, and he also says that these principles work for any car with any layout, with minor adjustments.

SPRINGS:

Stiffening front end =
Understeers in corners.
More grip, especially when exiting the corner.
Less traction on uneven surfaces.
Front tyres wear out faster
The car is easier to control
Front dips less during deceleration

Stiffening rear end=
Oversteers in corners.
Less grip, especially when exiting the corner.
Less grip on uneven surfaces.
Rear tyre wear increases.
Easier to control

Stiffening both =
Ride height can be dropped so the car gets underbody wacuum that glues it to the surface of the track.
Less grip on uneven surfaces.
Rear tyres wear more.
Easy to control.

Softening the front =
Oversteers in corners.
Less grip, especially when exiting the corner.
More grip on uneven surfaces.
Front tyre wear decreases
Controlling the car is harder
Could lead to rising the ride height at front.
Front dips more during deceleration

Softening the rear =
Understeers in corners.
More grip when exiting the corner.
More grip on uneven surface.
Less tyre wear
Controlling the car is harder
Could lead to rising ride height at rear

Softening both =
More grip on uneven surfaces.
Less tyre wear.
Car is harder to control.
Could lead to rising the ride height.

Ride height

Lowering the front - oversteers in corners.
Lowering the rear - understeers in corners.
Raising the front - understeers in corners.
Raising the rear - oversteers in corners.

Anti-Rollbar/Stabilizer

Stiffer front stabilizer =
Understeers in corners.
Less grip on uneven surfaces.
Easier to control the car.

Stiffer rear stabilizer =
Oversteers in corners.
Less grip especially when exiting the corner.
Less grip on uneven surfaces.
Rear tyre wear increases.
Easier to control the car.

Stiffening both stabilizers =
Less grip, especially when exciting the corner.
Increases tyre wear.
Easier to control the car.

Softer front stabilizer =
Oversteers in corners.
More grip when exiting the corner.
Less front tyre wear.
Harder to control the car.

Softer rear stabilizer =
Understeers in corners.
More grip on uneven surfaces.
More grip, especially when exiting the corner.
Less rear tyre wear.
Harder to control the car.

Softening both =
Could lead to raising the ride height.
More grip on uneven surfaces.
Less tyre wear.
Harder to control the car.

Bump dampers
prevents the wheel from moving upwards during bump.

Stiffening the front =
Understeers at uneven corners.
Increases front tyre wear.

Stiffening the rear =
Oversteers at uneven corners.
Less grip on uneven surfaces.
Increases rear tyre wear.

Stiffening both =
Less grip on uneven surfaces.
Tyre wear increases.
Harder to control the car on uneven surfaces.

Softening the front =
Oversteers on uneven corners.
Increases tyre wear at front.

Softening the rear =
Understeers on uneven corners.
More grip on uneven surfaces.
Rear tyre wear decreases.

Softening both =
More grip on uneven surfaces.
Less tyre wear.

Rebound dampers
prevents the wheel from moving downwards during bump.

Stiffening the front =
Understeers at the entrance and exit of the corner.
Increases front tyre wear.

Stiffening the rear =
Oversteers at the entrance and exit of the corner.
Less grip at the entrance and exit of the corner.

Stiffening both =
Easier to control the car.
Chassis is more stabile.
Difficult to find correct suspension balance.

Softening the front =
Oversteers at the entrance and exit of the corner.
Less tyre wear at front.

Softening the rear =
Understeers at the entrance and exit of the corner.
More grip at the entrance and exit of the corner.
Less rear tyre wear.

Softening both =
Car is harder to control.
Chassis rolls.
Springs have greater meaning in corners.

Suspension balance

Front-biased =
Understeers while braking, on the entrance of the corner.
Front wheels could lock up.
Longer braking distance.

Rear-biased =
Oversteers while braking, on the entrance of the corner.
Rear wheels could lock up.
Longer braking distance.

The translation might not be perfect ( I did my best, but there was some specific slang words that were unfathomable), but I've tested these principles in GT4, using the other Alpine, and they seem to work well.

 

[topgeardude]

why waste time tuning the A310?Its not a good car.

 

[Leonidae]

why it isn't a good car? because it's french, rear-engined thing, with underpowered fourpot-engine? that car has won multiple rallies in it's hey-day, and it was going head to head with other cars. so, basically, there's no good car or bad car, there are just cars that perform well in their own class.