Observations on suspension settings

[Z1-AV69]

But for your assessment to be correct that there is additional acceleration than push must be greater than drag?

I don't think so. Both downforce and drag are there. My test shows that minimum downforce is still faster than maximum downforce with nose up. That's why I have to count on the differences and not the absolute speed.

I'd use the crest on Cape Ring Periphery, find a starting line indicator and attempt to take each jump with the same driving line at crest and landing at a given speed. Take measurements using replay mode.

Puh, that would be difficult to measure right. I don't think I want to do that test myself...
From my experience a car with a good aerodynamic balance will always "fly well" and not point the nose to the sky. So I think the aero-modelling is at least good enough to get flying right. It's not only an increase in grip or something like that.

Edit: One more point: lifting the throttle right before the top of a hill will reduce flying more than the lower speed would suggest. So the different angle over the top does make a difference.

 

[budious]

If you removed the rear wing then the car shouldn't dip in the rear as it does to an extent then stops, it remains much more level off the crest. Also, if your conjecture is that the aero force pushes the car down range then it should be pushed further out after leaving the crest with higher settings, or possibly with no front downforce but the rear wing downforce changing the horizontal plane of the car; the latter being if you were to test application of downforce as being applied directly to the car rather than as a gravity modifier of the horizontal plane of the course itself.

 

[No_OBsT33R]

The higher front height low rear with low front DF and high rear. This lifts weight off the front tires, they contact the road less, this causes the front wheels to have a lower rolling resistance than the rear.

I'm just watching the assumptions fly, it's awesome. I'll collaborate the testing here with my resistance test shortly.

 

[Z1-AV69]

If you removed the rear wing then the car shouldn't dip in the rear as it does to an extent then stops, it remains much more level off the crest. Also, if your conjecture is that the aero force pushes the car down range then it should be pushed further out after leaving the crest with higher settings, or possibly with no front downforce but the rear wing downforce changing the horizontal plane of the car; the latter being if you were to test application of downforce as being applied directly to the car rather than as a gravity modifier of the horizontal plane of the course itself.

I'm afraid it's more complex. While the theory indeed suggests a car with more downforce would fly "forward" more, there is still drag slowing the car in the air and more downforce will push the car down too, both reducing the flying distance and therefor diminishing or probably even topping the effect of the forward pull.

What about the behavior when lifting throttle right before the top I edited into my last post? Full power on the rear wheels if only they have still contact can make the car kind of jump from the hilltop. It's noticeable on very powerful cars like the fully tuned MP4-12C. But imo thats not all. Lifting the throttle will make the rear come up and the nose go down, flattening the angle of the car over the road. The theory says this will reduce flying, which it does. If the downforce would be "applied" to the road surface and not the car, would this still happen? I don't think so.

 

[nomis3613]

If there really is downforce pushing the car forward then shouldn't someone with a clutch setup be able to disengage after hitting redline in top gear and the car continue to accelerate?

I don't think so. Both downforce and drag are there. My test shows that minimum downforce is still faster than maximum downforce with nose up. That's why I have to count on the differences and not the absolute speed.

I'm with Z1-AV69, the component of downforce in the forwards direction would cancel out only some of the drag. Otherwise you would have a GT5 perpetual motion machine!

Also, I don't see this explanation making much sense from a programming perspective, calculating an angular application of a force is more work than a static application...

Analyzing the physics of taking the car off a large jump with various aerodynamics settings would be a good control test study. If a car has no downforce front to rear then it tends to level out on a large jump. If the car only has a rear aero wing then it tends to dip the rear and raise the nose. How would it be affected with other combinations of downforce?

Good point about the ease of programming. But if you are trying to model drag and downforce of a car that was traveling up and down inclines, then a shortcut way might be to set the force directions relative to the chassis...(woops, physics rant! sorry!) Anyway, we'll never know how they programmed it of course.

As for the jumps testing, I don't think any results would carry much weight in this topic. Airborne cars may well be a special case for the GT5 programming, the could totally bypass the rest of the GT5 physics.

 

[Mudd]

When car designers use wind tunnel designs, some amount of down force is created by the shape of the car. When we lower the rear of the car and not the front, wouldn't we be taking away some of that downforce? Could that explain some of the top speed gain with nose-up?

 

[Johnnypenso]

Thats because the Zonda has great front traction and is tail happy, +15 front -30 rear would make the rear want to swing round especially under braking, am I right?

Not tried but if thats what does happen then it sort of proves the ride height is reversed!

Btw does GT Academy use on or offline physics?

Exactly!

 

[TT3AZ]

Okay, so how do we achieve maximum weight transfer to the rear axles by tuning the suspension?

Personly I use this settings, and the traction gets better:
Height: F (-all way down), R (all way up)
Spring rate: F (low as possible), R (low as possible)
Extension: F (10), R (5)
Compression: F (5), R (5)

These setting seems to work pretty well, but I dont understad the theory behind that, maybe some one can explain.

 

[st1sj]

Here is my contribution. Cappuccino RM. Autumn Ring Mini. 10 laps each run. Only altered ride height.

F height / R height / lap time (notes)

55 / 55 / 42.361
-10 / 55 / 42.256 (some understeer)
55 / -10 / 41.389 (some oversteer; most consistent)
-10 / -10 / 41.221 (fastest time but not consistent)

 

[Highlandor]

And even if it does turn out to be a 'cheap trick for speed that masks a lack of tuning ability', I still know I'll be faster than 99% of the people who play GT5 with or without the 'trick'
Good luck 👍

You may be faster on track, just a shame you're 4 months slower than others who knew about the ride height issue a long time ago.

You were even told this on page 1:

I started playing this game as a member of Team_Skills, and when PD started releasing the seasonal time trials Davey_Skills and the rest of the team were taking part in these events and quickly came to the same conclusion as you have. Everything like you say apart from Toe and Camber are backwards and before long in the time trials a lot of people were realizing that Davey_Skills was in fact setting the car up properly. It does look pretty ridiculous when you watch a replay seeing the rear of the car slammed to the floor with the front pointing towards the heavens, but surely it is just another small bug that can be fixed, because it is confusing a lot of people. For some reason they also found that a stiffer car was a lot faster than using softer settings, strange indeed.

Here's the thread GTP_Plato refers to:

https://www.gtplanet.net/forum/showthread.php?t=154708&page=2

I got over 80 gt friends on PSN, pretty much everyone has known about this for months - you need to deal with what works in the game for you, not what is supposed to happen in real life.

Welcome to the party....albiet, rather late.

 

[Stotty]

Okay, so how do we achieve maximum weight transfer to the rear axles by tuning the suspension?

Personly I use this settings, and the traction gets better:
Height: F (-all way down), R (all way up)
Spring rate: F (low as possible), R (low as possible)
Extension: F (10), R (5)
Compression: F (5), R (5)

These setting seems to work pretty well, but I dont understad the theory behind that, maybe some one can explain.

Overall, it's all about weight transfer... without any lateral pressure, increasing weight on a tyre contact patch will give you more grip.

Considering ride height 1st...

This is another example of why the ride height settings in GT5 don't work correctly!

It's all to do with polar moment of inertia...

In simple terms, polar moment of inertia refers to how difficult it is to get an object to rotate on an axis. The farther away from the axis of rotation the mass is, the harder it is to make it turn.

To be fast, what you want is a car that turns quickly, but doesn't become too unstable at the rear... the better the driver you are, the more instability you can manage.

So a low front/high rear ride height would be best for a front engined car as you'd be moving the axis of rotation towards the main bulk of the cars mass and thus making it easier to turn.

The main discussion in this thread is around whether the front and rear ride heights are the wrong way round, and polar moment of inertia supports this theory...

If low front high rear was correctly moddled, FF or FR cars would turn better with these settings applied, but they don't, they understeer more. Of course eveything is a balance, so a consequence of turning better would be decreased rear grip.

In your example you're getting increased rear grip with a low front high rear... and you should be getting the opposite.

Another example of why myself and others believe the ride height is transposed.

Considering the other settings...

Springs:
Soft springs will make it easier to transfer weight (less resistance to compression)... so as you get on the gas and the weight trys to transfer to the rear (think of how the nose of a powerful car rises as the throttle is depressed, transfering weight to the rear) it meets less resistance and therefore grip will improve as there's more weight pushing the tyre against the tarmac.

Dampers:
Only one of your settings is really relevent here (the others will have an effect, but you have them all at 5)... front extension (or re-bound). Rebound is how strongly the damper trys to return to it's natural position once it's stopped compressing.

So a high front rebound will always be trying to push the front of the car up and thus transfer weight to the rear.

Bound and rebound work against each other on opposing axles... so a strong front rebound (extension) would be cancelled out by a stong rear bound (compression).

Hope this makes sense

---------------------------------------------------------------------------------------

You may be faster on track, just a shame you're 4 months slower than others who knew about the ride height issue a long time ago.

You were even told this on page 1:



Here's the thread GTP_Plato refers to:

https://www.gtplanet.net/forum/showthread.php?t=154708&page=2

I got over 80 gt friends on PSN, pretty much everyone has known about this for months - you need to deal with what works in the game for you, not what is supposed to happen in real life.

Welcome to the party....albiet, rather late.

I've never claimed I 'discovered' this. I gave credit to Ramon for originally bringing it to my attention and also later to SKILLS when that post was linked.

And I'm not the one struggling to deal with this... read the thread.

Oh, and I have a full PSN friend list... thankfully you're not on it

Now kindly piss off and fail to get on someone else's nerves

 

[No_OBsT33R]

When car designers use wind tunnel designs, some amount of down force is created by the shape of the car. When we lower the rear of the car and not the front, wouldn't we be taking away some of that downforce? Could that explain some of the top speed gain with nose-up?

Yeah exactly. I'm pretty sure no matter what combo used there will always be body generated DF (measurable in resistance. The car has to push through the air) umm that's why I explained testing the resistance (with test already provided) would need be done with speed testing. You need to know what the body is doing vs the DF adjustments.

Test in the senerio that would generate the least DF (lowered DF settings coupled with a dropped rear and raised front) as the bottom baseline. The test in the senerio that would generate the most DF (highest DF settings coupled with a dropped front & raised rear)

Resistance Vs speed variation. Things should start getting clear.

I mentioned it. But I was ignored, and here we are....

My only question at this point is....

Does more air hitting the belly of the car with a raised front cause any increased "drag" or "lift" effect. Could they have eliminated the "lift" effect to patch the high speed wheelie cars of GT4?

Remember the high-speed wheelie cars from GT4 used DF settings to get the nose steady in the air while running jacked front ends and dropped stiff back ends. Seems they were taking advantage of the "lift" effect, & high-pressure on the rear end overpowering the weight on the front end, exploiting the games inability to flip cars.

Catch too much air under a car running high downforce & it will go airborne flipping

CLK GTR @ Le Mans & it happened to a Porsche also.

 

[Stotty]

My only question at this point is....

Does more air hitting the belly of the car with a raised front cause any increased "drag" or "lift" effect.

A lower front increases downforce (at the front and overall), so the opposite will apply.

--------------------------------------------------------------------------

Found some stuff on iRacing whilst wondering round the interweb which answers a few technical questions on the effect of ride height on drag and downforce...

Front:
Lower ride height: Lowers CG, front roll center, and increases rake. This will shift more weight to front, improving front tire grip and thus shifting the balance to less UNDERsteer and/or more OVERsteer and typically reduce aero drag and increase downforce.

Increased ride height: Raises CG, front roll center, and reduces rake. The change will shift weight to the rear, improving the grip of the tires at that end of the car and shifting the handling balance toward UNDERsteer and typically increase aero drag and increase downforce.

Rear:
Lower ride height: Lowers CG, rear roll center, and reduces rake. This will shift more weight to rear, improving front tire grip and thus shifting the balance to less OVERsteer and/or more UNDERsteer .

Increased ride height: Raises CG, rear roll center, and increases rake. The change will shift weight to the front, improving the grip of the tires at that end of the car and shifting the handling balance toward OVERsteer and increase downforce. Note the positive downforce effect may dominate the negative mechanical grip impacts and reduce oversteer, especially in high speed corners. Another potential downside – less rear braking available – may need to be addressed with an increase in brake bias to the front of the car


So a low front/high rear increases downforce and reduces drag... which is exactly what we experience when swapping front and rear ride height in GT5

Of course the data is circumstantial as it's from anpother game... though the circumstantial evidence does keep piling up and iRacing is regarded as the most accurate sim out there

 

[Mudd]

I'm pretty sure they did cut out the 'belly drag' for that reason, if you take a car with a big rear spoiler over a jump, (say the Minolta), the rear spoiler pulls the rear of the car down, but it stops rolling back as the spoiler gets low enough, there is no tendency to continue flipping backwards. I'm confident the air under the car no longer a factor.
So far, I do believe there are handling advantages to the "nose up" suspension tune, but I'm still not convinced that the ride height is actually backwards. It still feels to me like the raised front is simply changing the front spring rate by allowing more travel, although I have not completed every one of these tests myself yet.
Also, I certainly don't mean to ignore anyones thoughts already posted, I'm trying to keep up with this discussion, but it's a very active thread.

 

[HKS racer]

In GT5 you can go faster on the straight rising the front and lowering the rear because you reduce the car shaped downforce and probably in GT5 there is no air simulated effects under the car. As mentioned in the posts above seems PD removed it to "prevent" the GT4 wheelie glitch.
- What is a wheelie glitch in a videogame, in real life become a dangerous flip at high speed (CLK GTR) Real life cars and Ingeneers have always to deal with these effects.
So if PD remove air flow effects under the car, you don't need all that front downforce anymore to keep the car on track. If you remove such a big factor, the physics become fake.
- You don't need front downforce in the straight
- You can also rise the front and lower the rear to reduce the generated downforce from the bodyshape of the car and go faster in a stright line,
which doesn't make any sense in real life but it does in GT5.

Sorry for my English.

 

[Z1-AV69]

Here's the thread GTP_Plato refers to:

https://www.gtplanet.net/forum/showthread.php?t=154708&page=2

So the downforce pulling forward theory was already in this other thread, mostly undoubted. Does anyone really believe those setups would dominate the leaderboards if it would only be reduced drag by rake and the setting is reversed? I don't.

 

[No_OBsT33R]

I'm pretty sure they did cut out the 'belly drag' for that reason, if you take a car with a big rear spoiler over a jump, (say the Minolta), the rear spoiler pulls the rear of the car down, but it stops rolling back as the spoiler gets low enough, there is no tendency to continue flipping backwards. I'm confident the air under the car no longer a factor.
So far, I do believe there are handling advantages to the "nose up" suspension tune, but I'm still not convinced that the ride height is actually backwards. It still feels to me like the raised front is simply changing the front spring rate by allowing more travel, although I have not completed every one of these tests myself yet.
Also, I certainly don't mean to ignore anyones thoughts already posted, I'm trying to keep up with this discussion, but it's a very active thread.

That's my point. Thanks, Stotty missed it. Stotty I'm not talking about the effect of air over the car but under

 

[Sm0k3:D]

In GT5 you can go faster on the straight rising the front and lowering the rear because you reduce the car shaped downforce and probably in GT5 there is no air simulated effects under the car. As mentioned in the posts above seems PD removed it to "prevent" the GT4 wheelie glitch.

I don't think that PD take into acount the shape of the car in aerodynamics. I think it works in a basic and simplistic mode: More downforce = more grip.
No air simulated effects under the car and not either over the car. No matter if the car is going ahead or in reversal gear. I don't think even they use the friction coefficient for each car.
However i bet aerodynamics aren't the cause of this bug.

IMO the point is the weight transfer: When you're using a high front/low rear car, the weight can easily move from front to back, and this also works in a simplistic mode: more weight = more grip. But to avoid wheelie glitch there's always a minimum specific weight in the front end that can not be transfered to rear end. So you never lose all grip in front end. O maybe there's always a minimum specific grip in each tyre independtly of the weight on that tyre... or something like that.

 

[phil_75]

You may be faster on track, just a shame you're 4 months slower than others who knew about the ride height issue a long time ago.

You were even told this on page 1:



Here's the thread GTP_Plato refers to:

https://www.gtplanet.net/forum/showthread.php?t=154708&page=2

I got over 80 gt friends on PSN, pretty much everyone has known about this for months - you need to deal with what works in the game for you, not what is supposed to happen in real life.

Welcome to the party....albiet, rather late.

So it is no longer the real driving simulator, it is the made up car simulator and you are quite happy with that?

Aren't you supposed to be in th NFS forums!

I love and buy GT because it is supposed to be the "Real driving simulator" and now I have to wonder when racing online against people if they are using this glitch in which case they have no love of the game and what it stands for.

I will carry on as normal because I refuse to have my car pointing skywards, even if I come last I will have gotten more enjoyment than the spanners taking advantage of this **** UP!!!

I'm done!

 

[TT3AZ]

So a high front rebound will always be trying to push the front of the car up and thus transfer weight to the rear.

Bound and rebound work against each other on opposing axles... so a strong front rebound (extension) would be cancelled out by a stong rear bound (compression).

Okay, now i understand, because i use these settings for drag racing. So lets say i want to improve my weight transfer, can i run like front extension 10, and rear compression 1, would that increase force over the rear tires?

Regarding the height, high rear is because i want the back of the car to "jump" down and that will increase the preassure on the rear axle. Basicly i want my rear suspension to be as soft as possible so the rear jumps down when I accelerate.

 

[Mudd]

I think PD DID model in the car shape aero into the game, maybe only to an extent. Take any NASCAR around Daytona oval and establish consistent laps, remove all adjustable downforce and laps are faster. Now, lower the rear just a couple clicks and laptimes are even faster. I don't think that slight of a difference in front to rear hieght could translate to that much speed increase due to downforce "pushing" the car faster, but rather it is the decreased downforce on the rear allowing less resistance and in turn allowing greater speed.

 

[HKS racer]

I don't think that PD take into acount the shape of the car in aerodynamics. I think it works in a basic and simplistic mode: More downforce = more grip.
No air simulated effects under the car and not either over the car. No matter if the car is going ahead or in reversal gear. I don't think even they use the friction coefficient for each car.
However i bet aerodynamics aren't the cause of this bug.

IMO the point is the weight transfer: When you're using a high front/low rear car, the weight can easily move from front to back, and this also works in a simplistic mode: more weight = more grip. But to avoid wheelie glitch there's always a minimum specific weight in the front end that can not be transfered to rear end. So you never lose all grip in front end. O maybe there's always a minimum specific grip in each tyre independtly of the weight on that tyre... or something like that.

It could be, no air effects at all, no car shaped downforce, only taking adwantage of the weight transfer from the front end to the rear end without the drawback of too many airflow going under the car (which real life engineers have to deal with).

As a "fix" of the wheelie glitch PD used some values to keep the car on road indipendently from weight and/or grip. However in any case, with or without car shaping down force, if they aren't simulating any airflow at all we have a fake physics to deal with, screwing up all (or almost) real life tuning logic when someone's looking for the best performances.

The problem is in this game, with those settings (high front low rear) you can take advantage of weight transfer (and maybe other stuff) without real life drawbacks (which mean a CLK back flip, or simply a slower car on track because of drag (under the car) and reduced car shape downforce (over the car). So definitely GT5 fake aerodynamics are part of these bugs.

 

[esoxhntr]

Dampers:
Only one of your settings is really relevent here (the others will have an effect, but you have them all at 5)... front extension (or re-bound). Rebound is how strongly the damper trys to return to it's natural position once it's stopped compressing.

So a high front rebound will always be trying to push the front of the car up and thus transfer weight to the rear.

Bound and rebound work against each other on opposing axles... so a strong front rebound (extension) would be cancelled out by a stong rear bound (compression).

you have extension backwards. dampers settings work in terms of how difficult it is to compress (bound) or extend (re-bound) or, in other words how hard they 'resist' compression or extension. so, a high extension value resists the shock from extending (or re-bounding). a high compression value resists the shock from compressing.

so, to maximize the rate of weight transfer to the rear, you'd use low rear compression and low front extension.

 

[TT3AZ]

you have extension backwards. dampers settings work in terms of how difficult it is to compress (bound) or extend (re-bound) or, in other words how hard they 'resist' compression or extension. so, a high extension value resists the shock from extending (or re-bounding). a high compression value resists the shock from compressing.

so, to maximize the rate of weight transfer to the rear, you'd use low rear compression and low front extension.

Okay I will try this out.

 

[No_OBsT33R]

I think PD DID model in the car shape aero into the game, maybe only to an extent. Take any NASCAR around Daytona oval and establish consistent laps, remove all adjustable downforce and laps are faster. Now, lower the rear just a couple clicks and laptimes are even faster. I don't think that slight of a difference in front to rear hieght could translate to that much speed increase due to downforce "pushing" the car faster, but rather it is the decreased downforce on the rear allowing less resistance and in turn allowing greater speed.

This sounds most convincing. I think aero effects are simulated. o_O come on... Not simulated at all? In GT? Really, come on...

So it is no longer the real driving simulator, it is the made up car simulator and you are quite happy with that?

Aren't you supposed to be in th NFS forums!

I love and buy GT because it is supposed to be the "Real driving simulator" and now I have to wonder when racing online against people if they are using this glitch in which case they have no love of the game and what it stands for.

I will carry on as normal because I refuse to have my car pointing skywards, even if I come last I will have gotten more enjoyment than the spanners taking advantage of this **** UP!!!

I'm done!

X-infinity!!!!! Couldn't agree more.

Cheap trick for extra speed. I think it kills the game to use it and NFS is more suited to fanciers of this practice.

 

[TT3AZ]

you have extension backwards. dampers settings work in terms of how difficult it is to compress (bound) or extend (re-bound) or, in other words how hard they 'resist' compression or extension. so, a high extension value resists the shock from extending (or re-bounding). a high compression value resists the shock from compressing.

so, to maximize the rate of weight transfer to the rear, you'd use low rear compression and low front extension.

Well, the settings doesnt make sense to me, this is my old settings:

Height: F (-all way down), R (all way up)
Spring rate: F (low as possible), R (low as possible)
Extension: F (10), R (5)
Compression: F (5), R (5)

This is my new ones that I tested:
Personly I use this settings, and the traction gets better:
Height: F (-all way down), R (all way up)
Spring rate: F (low as possible), R (low as possible)
Extension: F (4), R (1)
Compression: F (2), R (2)

I get exactly the same weight transferment, because when I launch, the car jumps down in the rear as before, and I have the same traction.

I also tested to set front extension to 10, and rear compression to 10, I got similar weight transferment and traction. According to Scotty a hight rear compression would take out a high front extension, but it didnt show. Any tip?

This is what I found on the net, does this make sence?

FOR FR, RR, MR CARS
Spring Rate
~ Front As light as possible
~ Rear Between standard and mid-way
Ride Height
~ Front All the way up
~ Rear Standard
Dampening
~ Front 10 Bound 1 Re-bound
~ Rear 8 Bound 6 Re-bound
Camber
~ Front Usually stock (2 degrees)
~ Rear 0 degrees
Toe
~ Front 0 degrees
~ Rear 0 degrees
Summary
~ This setup asks the car to transmit as much weight as possible to the rear, where it can be used to pin the rear tyres to the track - hopefully.

Source: http://www.gtseriescenter.com/4dragH.htm

 

[Sm0k3:D]

I think PD DID model in the car shape aero into the game, maybe only to an extent. Take any NASCAR around Daytona oval and establish consistent laps, remove all adjustable downforce and laps are faster. Now, lower the rear just a couple clicks and laptimes are even faster. I don't think that slight of a difference in front to rear hieght could translate to that much speed increase due to downforce "pushing" the car faster, but rather it is the decreased downforce on the rear allowing less resistance and in turn allowing greater speed.

I don't think so. (But I really don't know, of course). If they did calculated, why you can go faster with more air under the car? It's know that the best position for speed is low front end / high rear end, because air can't easily enter under the car, but can easily exit. This causes a negative presure under the car and increases the grip. (Think about chaparral 2j system)
I think downforce = more grip = less speed calculated in the more simplistic way.
Or maybe more grip = more friction (that causes less speed)

They didn't calculate even the tyre grip correctly (we all know the wet track bug: Slicks have more grip than wet tyres) or the compound durability... And this also induces me to think that if they didn't create a nice physic formula for that they didn't be able to create an aerodinamic variable in their formula. Even if they aded the aerodynamic variable, there's a mistake in the formula. And this mistake becames obvious when you take physics to extreme conditions.

It is just a mistake in the grip formulas: You have enough grip to turn your car without weight in the front end. (or front heigh/rear heigh are backward) because the minimum grip or minimum weight it's misscalculated.

GT5 physics should be revised and corrected. I don't think physic is a fake... just is wrong.

 

[Stotty]

Guys, just to be absolutely clear as this thread seems to have taken a tangent towards the aerodynamic effects...

The front high/rear low setting wasn't really about delivering a higher top speed... it's first and foremost a setting to cure/kill understeer. The slight top speed gain is a nice side effect, but the understeer cure is far more important!

------------------------------------------------------------------------------------

I'm not going to call out individuals, but there are people posting in here who really don't know what they are talking about... anyone who thinks raising the front ride height is simply creating harder/softer spring rate, or that this is therefore allowing more weight transfer etc, just don't understand the fundamentals of car suspension in the real world.

If you don't know what you're talking about it's always better to shut up or ask a question than make a stupid statement!

 

[Dr_Watson]

Okay, now i understand, because i use these settings for drag racing. So lets say i want to improve my weight transfer, can i run like front extension 10, and rear compression 1, would that increase force over the rear tires?

The stiff front extension should cancel out the soft rear compression.

                           .
       -----  -+---+-     / \
       , - `   |   |       |
       , - `   |   |       |
       , - `   |   |    
       , - `   '==='    Rebound
       , - `    | |        
       , - `    | |        |
       , - `    | |        |
       -----  --+-+--     \ /
                           '
       -----  -+---+-    -----
       , - `   |   |       |
       , - `   |   |       
       , - `   '==='    Neutral
       , - `    | |        
       , - `    | |        |
       -----  --+-+--    -----
                           |
       -----  -+---+-     \ /
       , - `   |   |       '
       , - `   '==='     Bound 
       , - `    | |        . 
       -----  --+-+--     / \
                           |

You've got a spring and a damper which absorbs energy from the spring's bound and rebound. The softer the compression of the damper the more vertical travel the spring will be allowed, and the more energy will be absorbed. Like punching a board vs punching a pillow. the board *hurts* more because newtons law is giving you the equal and opposite business. However the pillow has some *give* as it decelerates your punch slower using more travel, saving your hand from getting the full force. A stiff compression value (10) on the damper would create a board, preventing the spring from compressing. While a soft (1) damper would be the pillow, bleeding off energy while the sprung mass decelerates slower using more travel.

Once the spring has been compressed it wants to rebound back toward it's neutral position. The stiffness of the damper extension determines how difficult it is for the spring to do this and how much energy is bled off in the process. The stiffer the extension the harder it is for the spring to rebound.

So when you leave the line and weight tries to transfer rearward the rear springs and dampers will compress. This means you're right that soft springs and soft damper compression will allow the most weight to transfer to the rear axle (combined with a stiff extension value so the spring doesn't just rebound the weight back forward).
However in the front the opposite is happening. The weight is leaving the axle and so you want a soft extension to allow the most spring to stretch while the front end lifts.

So drag shock damping is more like 10/1 front, 1/10 rear (compression/extension).

 

[No_OBsT33R]

I don't think so. (But I really don't know, of course). If they did calculated, why you can go faster with more air under the car? It's know that the best position for speed is low front end / high rear end, because air can't easily enter under the car, but can easily exit. This causes a negative presure under the car and increases the grip. (Think about chaparral 2j system)
I think downforce = more grip = less speed calculated in the more simplistic way.
Or maybe more grip = more friction (that causes less speed)

They didn't calculate even the tyre grip correctly (we all know the wet track bug: Slicks have more grip than wet tyres) or the compound durability... And this also induces me to think that if they didn't create a nice physic formula for that they didn't be able to create an aerodinamic variable in their formula. Even if they aded the aerodynamic variable, there's a mistake in the formula. And this mistake becames obvious when you take physics to extreme conditions.

It is just a mistake in the grip formulas: You have enough grip to turn your car without weight in the front end. (or front heigh/rear heigh are backward) because the minimum grip or minimum weight it's misscalculated.

GT5 physics should be revised and corrected. I don't think physic is a fake... just is wrong.

I agree to disagree I most positive aero effects are implemented. I've already calculated increased wind resistance.

Look if it's all this grip thing run the same test in R tires & then S tires, look and see if your at the same speed at the same rpm at low med high rpm's..... I would put my money that your going to hit the same speed, what's that tell yah?