General Tuning Guide (Updated 1.09)

[eclipsee]

Anyway, without wishing to question either yourself of Hami, I've found an inconsistency between your descriptions.
It's regarding front toe.

Your guide states:
Front toe in (+ Slider to the right)
Pros: Improved straight line stability. Increased mid corner grip
Cons: Reduced grip on turn in

Front toe out (- Slider to the left)
Pros: Increased grip on turn in
Cons: Less stable at speed. Reduced mid corner grip.

And Hami's guide states:
Toe Angle
- Front toe-in will increase entry turn in, but also reduces mid-corner to exit grip
- Front toe-out will increase mid-corner to exit grip, but also reduces entry turn in

Hami is right, without any doubt.

 

[DolHaus]

Hami is right, without any doubt.

Based on what evidence?

 

[eclipsee]

Based on what evidence?

My times.

 

[DolHaus]

My times.

Your times prove nothing as far as who's description of toe is correct.

Go get a car, set it to 0.0/0.0 camber.
Drive that car at 0.00 front toe to get a feel for how fast it turns in and at what point in the corner they let go
Set the front toe to -0.15 (toe out) and go throw the car into a corner, notice how the car darts in and then loses grip mid corner?
Set the front toe to 0.15 (toe in) and repeat the test, notice how the car is slower to react on turn in but holds traction better in the mid corner?

 

[eclipsee]

Your times prove nothing as far as who's description of toe is correct.

People tune his cars to make them faster and the stopwatch rules the game, a faster car means that its setup is better, I use Hami's toe description to make my cars faster, hence his description is right to me.

Go get a car, set it to 0.0/0.0 camber.
Drive that car at 0.00 front toe to get a feel for how fast it turns in and at what point in the corner they let go
Set the front toe to -0.15 (toe out) and go throw the car into a corner, notice how the car darts in and then loses grip mid corner?
Set the front toe to 0.15 (toe in) and repeat the test, notice how the car is slower to react on turn in but holds traction better in the mid corner?

Well, I can feel just the opposite of what you said.

 

[DolHaus]

People tune his cars to make them faster and the stopwatch rules the game, a faster car means that its setup is better, I use Hami's toe description to make my cars faster, hence his description is right to me.


Well, I can feel just the opposite of what you said.

I'm not going to get into and argument based on what someone feels.

As far as my description is concerned it is both accurate in terms of physics and application, if you don't agree then feel free to do as you like

 

[Aussie_HSV]

Hi @DolHaus
I've returned to pick your brain briefly.

A quick question regarding braking.
More specifically, a fairly aggressive front-end (I think) turn-in causing a rear-end twitch when I apply the brakes while cornering.
My setup seems fine and suits my driving style quite well, but whenever I'm using some steering angle and apply the brakes mid-corner, it's causing the nose to dive in and I find myself needing to change driving lines so as to not cut the corner.
It also causes the rear-end to twitch, although only slightly, but it's another thing I need to compensate for.
I'm thinking this twitch is due to the nose diving in towards the inside of the corner though.
So more a symptom, not really the cause.

It calms down by lowering both brake bias numbers, but I think I'm only masking the symptoms, not actually correcting the cause of the problem.

It's not a major issue and I can live with it, but it's something I'ld like to tune out or at least learn how to try to tune out, but can't find an easy answer without some fairly major changes to my setup.

Any quick pointers as to what's causing this to happen would be appreciated.

 

[DolHaus]

Hi @DolHaus
I've returned to pick your brain briefly.

A quick question regarding braking.
More specifically, a fairly aggressive front-end (I think) turn-in causing a rear-end twitch when I apply the brakes while cornering.
My setup seems fine and suits my driving style quite well, but whenever I'm using some steering angle and apply the brakes mid-corner, it's causing the nose to dive in and I find myself needing to change driving lines so as to not cut the corner.
It also causes the rear-end to twitch, although only slightly, but it's another thing I need to compensate for.
I'm thinking this twitch is due to the nose diving in towards the inside of the corner though.
So more a symptom, not really the cause.

It calms down by lowering both brake bias numbers, but I think I'm only masking the symptoms, not actually correcting the cause of the problem.

It's not a major issue and I can live with it, but it's something I'ld like to tune out or at least learn how to try to tune out, but can't find an easy answer without some fairly major changes to my setup.

Any quick pointers as to what's causing this to happen would be appreciated.

It sounds like a weight transfer issue to me so I would look at the front damper compression and the rear damper extension. From the description it sounds like when you are hitting the brakes too much weight is being transferred onto the front wheels too quickly which is causing the front to dive and the rear to lose grip.
To deal with this I would start by increasing the rear damper extension value to slow the forward weight transfer, if I couldn't quite get the desired effect by using the rear extension then I would start to increase the front damper compression to achieve the same basic result.
If this didn't solve the problem then I would start playing with the LSD and trying to bring all three values closer together to force the diff into being more constant rather than having the outside wheel changing speed violently every time you go from throttle to brake.
Lowering the brake bias will dilute the problem a bit by reducing the speed of the weight transfer but it will also make your brakes less effective as a result, this can be fine on some tracks where maintaining momentum is important but on others where you need to shed a lot of speed quickly it will harm your performance.
Another thing that can stop the brakes being so vicious is using the standard brakes rather than the racing upgrade, on some cars this is the best way to solve the problem so don't always assume the upgrade is better, sometimes they are just too snatchy and remove the ability to make small braking corrections without dropping the proverbial anchor 👍

 

[Aussie_HSV]

Excellent mate.
Appreciate the diagnosis. 👍

Yeh, I figured lowering the brake numbers was really only a band-aid solution.
Nice thought about dropping the racing brakes back to standards though.
I'll keep that in the back of my mind for another day.

As it stands, I've already pushed the front comp. and rear ext. dampers quite high.
Questionably a bit too high for that matter.
Diff has almost nothing in it as far as spread is concerned either.
Initial is very low, and then it's only a few clicks up to evenly matched accel. and decel. figures.

But I have plenty of room to move with the front springs.
So using your theory of weight transfer being the issue, I'll step that up incrementally and see if that starts heading the setup in the right direction.

Cheers.

 

[DolHaus]

Excellent mate.
Appreciate the diagnosis. 👍

Yeh, I figured lowering the brake numbers was really only a band-aid solution.
Nice thought about dropping the racing brakes back to standards though.
I'll keep that in the back of my mind for another day.

As it stands, I've already pushed the front comp. and rear ext. dampers quite high.
Questionably a bit too high for that matter.
Diff has almost nothing in it as far as spread is concerned either.
Initial is very low, and then it's only a few clicks up to evenly matched accel. and decel. figures.

But I have plenty of room to move with the front springs.
So using your theory of weight transfer being the issue, I'll step that up incrementally and see if that starts heading the setup in the right direction.

Cheers.

Try bumping the spring rate up and do the same with the diff, low values can cause sudden and violent changes to wheel speed leading to instability. When adjusting your spring rate make a mental note of how the little blue bars (in the centre below the Front/Rear labels) are scaled in relation to each other, if you raise the front spring by itself then you will change the balance of the car and most likely get increased understeer as a result. If you increase both so that the little bars are in roughly similar relative positions then the balance of the car won't be as affected and you'll save yourself some time.

 

[Aussie_HSV]

Will do, cheers. 👍

 

[ANorthernSoul]

I'm not going to get into and argument based on what someone feels.

As far as my description is concerned it is both accurate in terms of physics and application, if you don't agree then feel free to do as you like

Just to back your point up, as it was bugging me.

You should break the grip levels into the phases of the corner, entry-mid-exit. Now at entry grip levels between the two front tyres is even and the most effective tyre would be the inside one, therefore toe-out increases the initial turn-in as the wheel wheel is primarily focused in the direction (to some degree)
At mid corner the lateral load has shifted to the outside wheel, and now holds most grip. Running toe-out means that the outside tyre will be focus away from the corner, causing understeer; running toe-in focuses the tyre on the outside towards the corner, providing more grip and less scrub.
And finally on corner exit lateral load should have balanced and the grip should now be even, providing more grip to the inside wheel where toe-out would be beneficial.

However there isn't a correct way in which you should tune it, it does come down to feel and driving style somewhat. Personally I like to run toe-in, the extra grip mid-corner give me more confidence on the exit; and a less responsive turn-in helps me hit the apex more regularly.

Source: University degree and hours of racing.

 

[DolHaus]

Just to back your point up, as it was bugging me.

You should break the grip levels into the phases of the corner, entry-mid-exit. Now at entry grip levels between the two front tyres is even and the most effective tyre would be the inside one, therefore toe-out increases the initial turn-in as the wheel wheel is primarily focused in the direction (to some degree)
At mid corner the lateral load has shifted to the outside wheel, and now holds most grip. Running toe-out means that the outside tyre will be focus away from the corner, causing understeer; running toe-in focuses the tyre on the outside towards the corner, providing more grip and less scrub.
And finally on corner exit lateral load should have balanced and the grip should now be even, providing more grip to the inside wheel where toe-out would be beneficial.

However there isn't a correct way in which you should tune it, it does come down to feel and driving style somewhat. Personally I like to run toe-in, the extra grip mid-corner give me more confidence on the exit; and a less responsive turn-in helps me hit the apex more regularly.

Source: University degree and hours of racing.

My thoughts exactly, very well explained 👍

 

[FSportIS]

In general, what is the difference between tunes gear toward DS3 users vs. wheel users? Can wheel users use DS3 tunes and have similar handling like the DS3 users? If not, how should we adjust the DS3 tunes for wheel users?

 

[DolHaus]

In general, what is the difference between tunes gear toward DS3 users vs. wheel users? Can wheel users use DS3 tunes and have similar handling like the DS3 users? If not, how should we adjust the DS3 tunes for wheel users?

I honestly couldn't tell you the difference as I've never owned a wheel.
As for whether DS3 tunes can be used with a wheel and vice versa, they are completely interchangeable and will work on both 👍

 

[richidoo]

Guys, check out www.xcalracing.com/live/ for tonight's season finale from charlotte motor speed way. race starts at 7:30pm EST. BE THERE! Lol I'm in the 03 as usual. See you there.

 

[DolHaus]

Guys, check out www.xcalracing.com/live/ for tonight's season finale from charlotte motor speed way. race starts at 7:30pm EST. BE THERE! Lol I'm in the 03 as usual. See you there.

Err.... What?

 

[Bowtie52]

Thanks DolHaus for all the work you've put in on this tuning guide. You've probebley already covered this. Can you tell me on extension dampers is it the higher the number the stiffer or the faster it is? Thanks again man.

 

[DolHaus]

Thanks DolHaus for all the work you've put in on this tuning guide. You've probebley already covered this. Can you tell me on extension dampers is it the higher the number the stiffer or the faster it is? Thanks again man.

The higher the Damper number, the more it resists change and slower it will react.

Higher compression value = Compresses more slowly
Higher extension value = Extends more slowly

👍

 

[Bowtie52]

Thank you 👍

 

[Harsk100]

I got one question: Imagine if I buy an Dodge Challenger R/T'70. I tune it to the max and I put Racing Tires in it. If I put -1.00 on the rear toe angle and + 0.30 on the front toe angle, then I'll get less grip on the front and more oversteer in rear toe angle, right?

 

[DolHaus]

I got one question: Imagine if I buy an Dodge Challenger R/T'70. I tune it to the max and I put Racing Tires in it. If I put -1.00 on the rear toe angle and + 0.30 on the front toe angle, then I'll get less grip on the front and more oversteer in rear toe angle, right?

You'll end up with an awful mess is what you'll end up with

I would never recommend putting that amount of Toe Out (-) on the rear of any car, specially not a high powered rear wheel drive muscle car. As a basic rule you should never really run Toe Out on the rear wheels with the possible exceptions of FF cars and maybe 4WD's in extreme circumstances, even then I wouldn't use more than -0.20 at the very most.

The front Toe In (+) will give you less front end grip during corner entry but improved mid corner grip.

Setting the toe as you have described will make the car very unstable and impossible to control, you'll get a bunch of understeer on turn in and then the car will rotate suddenly and unexpectedly. The large amounts you are using will cause a lot of tire scrub and slow you down in a straight line and then make the car uncontrollable in the corners, you would see no performance gains from that whatsoever.

 

[Harsk100]

You'll end up with an awful mess is what you'll end up with

I would never recommend putting that amount of Toe Out (-) on the rear of any car, specially not a high powered rear wheel drive muscle car. As a basic rule you should never really run Toe Out on the rear wheels with the possible exceptions of FF cars and maybe 4WD's in extreme circumstances, even then I wouldn't use more than -0.20 at the very most.

The front Toe In (+) will give you less front end grip during corner entry but improved mid corner grip.

Setting the toe as you have described will make the car very unstable and impossible to control, you'll get a bunch of understeer on turn in and then the car will rotate suddenly and unexpectedly. The large amounts you are using will cause a lot of tire scrub and slow you down in a straight line and then make the car uncontrollable in the corners, you would see no performance gains from that whatsoever.

So, it is recommended to leave the toe angle of Challenger in 0.00, right? I want to reduce the oversteer of the Challenger because I drive with SRF off now. All aids off except ABS at 1.

 

[DolHaus]

So, it is recommended to leave the toe angle of Challenger in 0.00, right? I want to reduce the oversteer of the Challenger because I drive with SRF off now. All aids off except ABS at 1.

If you want to reduce oversteer then I would recommend putting some Toe In (+) on the rear, 0.00 would be a setting more suited to adding rotation rather than stability.
I'd say start at 0.20, take it for a test drive and see if the car is stable enough for you.
If not, try 0.30 and retest. Keep increasing in increments of 0.05 until you find what suits you best.
If when you set the car to 0.20 it feels too stable and is understeering as a result then try 0.15 and decrease in increments of 5 until you find the right setting for you.

I wouldn't recommend the Dodge Challenger '70 as a car to learn tuning or driving without aids, its very old and badly designed for circuit racing so it will never be that great. I would say you are better off learning in something modern that responds well to tuning and will give you more feedback. Good starter cars would be the Mazda Miata/MX5/Eunos Roadster, the Honda S2000 and the Toyota GT86/Subaru BRZ/Scion FRS.
Racing tires will also teach you nothing about how the car is responding to tuning changes, they're so grippy that they hide all but the worst tuning flaws and to get the best from them you need a race car chassis rather than a road car. Best tires to start learning with would probably be Sport Hard/Medium, they will help to highlight problems and show where the car can be improved.

 

[Harsk100]

But

If you want to reduce oversteer then I would recommend putting some Toe In (+) on the rear, 0.00 would be a setting more suited to adding rotation rather than stability.
I'd say start at 0.20, take it for a test drive and see if the car is stable enough for you.
If not, try 0.30 and retest. Keep increasing in increments of 0.05 until you find what suits you best.
If when you set the car to 0.20 it feels too stable and is understeering as a result then try 0.15 and decrease in increments of 5 until you find the right setting for you.

I wouldn't recommend the Dodge Challenger '70 as a car to learn tuning or driving without aids, its very old and badly designed for circuit racing so it will never be that great. I would say you are better off learning in something modern that responds well to tuning and will give you more feedback. Good starter cars would be the Mazda Miata/MX5/Eunos Roadster, the Honda S2000 and the Toyota GT86/Subaru BRZ/Scion FRS.
Racing tires will also teach you nothing about how the car is responding to tuning changes, they're so grippy that they hide all but the worst tuning flaws and to get the best from them you need a race car chassis rather than a road car. Best tires to start learning with would probably be Sport Hard/Medium, they will help to highlight problems and show where the car can be improved.

And the relation in Dodge Challenger Race Car'70?

 

[DolHaus]

But

And the relation in Dodge Challenger Race Car'70?

Its better than the road car but its still a 70's muscle car, strong in a straight line but a bit unwieldy in the corners. Its not a terrible car but if you are looking to learn something about tuning then I would start elsewhere.

 

[Motor City Hami]

wrong thread. sorry

 

[gt4rulez]

Ok so i have a question for you regarding Skyline GTRs
I've been using them alot for various races since i started playing gt games and i like them alot, damn i even bought one and use it on the track in real life!

they are great cars to drive because they can put large amounts of power on the ground even during cornering with the right setup wich is good for fast corner exits. with some front and rear diff tuning they seem to lose alot of their understeer problems, also i love how the stock center diff is working. (basically what it does it only uses the front wheels when it really needs them during acceleration, but tries to be as rwd as possible during other conditions with a slight bit of oversteer)

one thing about them though (no matter if its an r32 r33 or R34, even the 4wd touring car versions wich have plenty of downforce have this problem), i love to brake late and hard into a corner but the front outside tire looses grip quite fast while turning into a corner. (tire meter will get dark orange and as soon as that happends it will get understeer till you slowed down enough to let it cool down) it can ruin lap times if you miss the apex because of the understeer on the corner entry. mid corner and corner exit it feels very stable, almost like on rails.

what are your thoughts about this? decreasing the front brakes wont be a good solution i think, usually i use the stock settings for them (5-5).
i've tried to decrease and increase the deceleration settings for the front diff and somehow the higher decel settings seem to improve the braking while cornering a bit (and it makes not much sense because it gets locked more :S). although i set the initial torque and accel rates for the front very low. (notice that most stock gtr's only use a rear limited slip diff)

im trying to figure out what happends and how to fight this problem to improve my set ups and lap times. is it because the front spring rates are too low? should i use more camber? toe in in the front perhaps? shift the center of gravity by adjusting the ride height? or maybe slow down the weight transfer by adjusting the dampers?

basically how can you get the most out of that outside front tire while braking into a corner. note that they have like a +/- 54-46 weight distrubution. any ideas?

 

[DolHaus]

Ok so i have a question for you regarding Skyline GTRs
I've been using them alot for various races since i started playing gt games and i like them alot, damn i even bought one and use it on the track in real life!

they are great cars to drive because they can put large amounts of power on the ground even during cornering with the right setup wich is good for fast corner exits. with some front and rear diff tuning they seem to lose alot of their understeer problems, also i love how the stock center diff is working. (basically what it does it only uses the front wheels when it really needs them during acceleration, but tries to be as rwd as possible during other conditions with a slight bit of oversteer)

one thing about them though (no matter if its an r32 r33 or R34, even the 4wd touring car versions wich have plenty of downforce have this problem), i love to brake late and hard into a corner but the front outside tire looses grip quite fast while turning into a corner. (tire meter will get dark orange and as soon as that happends it will get understeer till you slowed down enough to let it cool down) it can ruin lap times if you miss the apex because of the understeer on the corner entry. mid corner and corner exit it feels very stable, almost like on rails.

what are your thoughts about this? decreasing the front brakes wont be a good solution i think, usually i use the stock settings for them (5-5).
i've tried to decrease and increase the deceleration settings for the front diff and somehow the higher decel settings seem to improve the braking while cornering a bit (and it makes not much sense because it gets locked more :S). although i set the initial torque and accel rates for the front very low. (notice that most stock gtr's only use a rear limited slip diff)

im trying to figure out what happends and how to fight this problem to improve my set ups and lap times. is it because the front spring rates are too low? should i use more camber? toe in in the front perhaps? shift the center of gravity by adjusting the ride height? or maybe slow down the weight transfer by adjusting the dampers?

basically how can you get the most out of that outside front tire while braking into a corner. note that they have like a +/- 54-46 weight distrubution. any ideas?

Ok, the way to find a solution to the problem is to analyze what forces are acting upon the tire at any given moment and how that effects traction. A tire has a fixed amount of force that it can deal with before it becomes overcome and loses traction, these forces come in the form of linear forces (acceleration/braking) and lateral forces (cornering). These forces are rarely separate and it is often a combination of factors that cause problems, if any one force exceeds the peak load of a tire then it loses grip and won't regain it until the forces are reduced and balance can return.

Lets have a look at what the different drivetrains are having to deal with in terms of force and how this can manifest itself.

Front Wheel Drive

Front Wheels: Power Delivery, braking force, turning force
Rear Wheels: Cornering load, braking force

Common Issues: Understeer when accelerating out of corners
Reason: The front wheels are trying to handle the load of both linear acceleration and lateral cornering force which can quickly exceed the limits of the tire.
Fix: Alterations to driving style so you are separating acceleration and turning is generally the best solution. Tuning solutions basically revolve around trying to stop the weight of the car being transferred onto the rear wheels by increasing front damper extension rates and increasing rear damper compression as well as maybe adding front ballast.


Rear Wheel Drive

Front Wheels: Braking force, turning force
Rear Wheels: Power delivery, cornering load, braking force

Common Issues: Oversteer when accelerating out of corners
Reason: The outside rear tire is under the most load at the stage where you are getting ready to apply the power due to the way the weight has shifted backwards and outwards, when you add in the extra force of acceleration the tire gets overloaded and loses traction.
Fix: Lowering the LSD Accel will allow extra power to be shifted to the inside wheel meaning that the outside wheel has less force to deal with. Balancing the rear compression and stiffening the front extension will allow the suspension to control the amount of load being transferred to the tires better and further reduce the overall load.


4WD

Front Wheels: Power Delivery, braking force, turning force
Rear Wheels: Power delivery, cornering load, braking force

Common Issues: Understeer
Reason: Because the power is being sent to all four wheels they all have to deal with extra load during every situation, this means that they generally have a much narrower tolerance to input. This said, when they do lose grip it is easier to redistribute the load and control can be regained faster. The more BHP/Torque you put into a 4wd system, the worse the understeer becomes because all that extra acceleration force just removes the ability to turn efficiently.
Fix: It all comes down to deciding how much force you want acting on each axle at any given moment, this can be adjusted by using your LSD's and your Torque Distributing Center Differential (TDCD). If the front wheels are getting overcome then you need to shift some power to the rear, if the rear wheels are getting overcome then send more power to the front. If the outside wheel is losing grip then lower the appropriate LSD setting depending on the input, if the inside wheel is losing grip then increase the appropriate LSD setting.



I think what is happening with your car is that the stock Variable TDCD is getting overwhelmed and not giving you enough consistency, they work great in real life but much like Mitsubishi's AYC they don't work that well in the game when pushed to the limit and/or given extra BHP/Torque.

The key to driving a 4wd is to be slow on entry so you don't overload the front tires and then use all the extra traction through mid corner and exit: Slow in - Fast out.
They don't really suit late braking as even though they have the grip to get stopped they can't use the violent weight transfer to get rotated efficiently, the tires just get overwhelmed and all you get is understeer. You really have to adapt your driving style to make the most of the cars strengths rather than trying to force it to do what you want, its all about making the style of your entry fit with how you can best exit the corner rather than the other way around.

(Another thing to check if you are running front camber then you should be running some front Toe Out (-) to correct for the initial understeer on turn in that camber gives. Its hard to tell what the issue might be without seeing the setup)

 

[gt4rulez]

Thanks for your reply

For example this is what i use for my Skyline GTR R33 Touring Car
its fully tuned/upgraded + oil change, except it uses a stage 2 turbo kit, i use racing hard tires
i try to tune them on tsubuka cause thats were the problem really shows itself.
with skid recovery on its not that hard to get really low 0.50.1xx lap times with it, did a few 0.49.9xx aswell again with racing hard tires.
with skid recovery off im using center diff 40 - 60 and it will be around a second slower each lap and alot more tail happy.
also using ds3 cause for now i dont have a playseat for the g27

suspension settings
Front - Rear

ride height 65 - 65
Spring rate 12.33 - 10.14
Compression 5 - 4
Decompression 3 -5
stabi's 5 -4
camber 2.2 - 2.0
toe angle -0.07 - +0.60

Brakes 5 - 6

Diffs (what i did is make sure that in very tight corners the tires heat up pretty much equally while going full throttle out of the corner. its just enough to keep the inside tires from spinning out first. skid recovery on = stock center diff, skid recovery off = 40-60)
initial 5 -7
accel 12 - 17
decel 30 - 5

downforce 350 - 350 (really adding more rear downforce only makes understeer worse)

Ballast 27kg all the way in the back to get a slightly better weight disturbution.

i didnt really tune the gearbox for the track, for the first 5 gear ratios im using the ratio's that OS Giken uses in real life for their close ratio gear set that can be used in the stock 5 speed gearbox. 6th is like just another gear to gain even more top speed.

speed 320kmh
1st 2.695
2nd 1.703
3rd 1.236
4th 1.000
5th 0.826
6th 0.700

final 4.545

the first 2 gears are pretty long but it helps getting 900hp 976nm to the ground.
all other driving aids are off abs just 1