Observations on suspension settings

[Stotty]

You can of course choose to see the effects how you wish, but at the end of the day logic, based on real life understanding of suspension and aerodynamics, suggests that high front/low rear settings are having the opposite effect to real life... so there's either a big hole in the physics model or someone has made a mistake in the programming.

Suggesting that the suspension height is somehow effecting the spring rate is, IMO, a red herring. Someone has said that in their opinion 'raising the front suspension by 25% is the equivalent of softening the spring rate by 25%', and this is why it's having the effect of reducing understeer. This, IMO, is just a silly assumption. If this was the case, understeer could be cured by simply fully softening the front springs and fully hardening the rears... but this does not have that effect... or if it does, it bring so much 'wooliness' to the front end that it totally negates the benefits.

At least from my side, the high front low rear settings aren't there to create more speed (though that is a nice side effect, and is an accurate representation of real aerodynamics in a simplified form), only to make the cars handle correctly... by handle correctly, I mean not understeer permanently whatever you do with the throttle or brake pedal. Yes, the cars can be made to oversteer with other settings, but only throttle induced power oversteer.

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'

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

To be honest, I'm not minded to spend a lot of time on 'empirical testing'. I have enough understand of the physics of car handling, I'm a good enough driver (both in the game and in real life) and I've enough experience of tuning in previous itterations of the game to feel the effects and know they are driving the right outcome.

I'll keep popping in to see if anyone has managed to 'prove' anything either way. But I suspect that whenever someone claims to have 'proven' something, someone else will come up with an esoteric reason why the proof could be doubted! There are just so many variables going on here I think you'll be going round in circles forever. Sometimes you just have to believe what's staring you straight in the face

Good luck 👍

 

[chuyler1]

I'll keep popping in to see if anyone has managed to 'prove' anything either way. But I suspect that whenever someone claims to have 'proven' something, someone else will come up with an esoteric reason why the proof could be doubted! There are just so many variables going on here I think you'll be going round in circles forever. Sometimes you just have to believe what's staring you straight in the face

This is so true with just about any internet discussion. What it comes down to is trial and error. Try things out yourself and see if it makes your car behave better. If you don't achieve the desirable results by adjusting settings one way, try going the other way. Whether the settings are reversed or not, the best tune is going to come from the player who spends the most time experimenting and who can readily identify improvements vs steps backward.

 

[jack5428]

this isnt a trick or glitch. as far as backwards...well im totally use to it and if i want to change something about my car i have a good idea usually what to change. sometimes if you want a behavior out of the rear of the car you can change a setting on the front of the car but that doesnt mean its backwards.

nope you can keep your backward thoughts to yourselves. hahaha

as far as this tuning technique darnit i thought i was the only one who knew this! actually i cant even see on my own vehicles if i raise the front up high...was disapointed it didnt look more like the Buick Special. speaking of the Buick Special i think that car stock on racing soft tires feels like a finely tuned race car. shocked me how sweet it was to drive right after i won it.

yeah i think you will find not a whole lot of cars get any benifit from rear low front high. the understeery bad to drive ones benifit the most for sure. hard to find the ideal front ride height. like looking for a needle in a haystack. my least favorite tuning setting for sure to discover. usually its so specific just plus or minus one sucks.

only worth a seasonal TT top ten effort for me to tune that hard and specific every setting of a car perfectly with only one goal for each setting...to reduce lap times.

ive enjoyed the PSN break but enough is enough! i want to TT and learn some cool new things! crazy ways to take corners i never thought of yet! new tune "tricks" or "glitches" or "bugs"....hahaha just tuning settings dudes nothing more than that.

 

[phil_75]

I'm still not 100% sure if other suspension settings are reversed (or have the reverse effect of what they should have), but I'm convinced ride height is, as are others with a similar experience with GT games.

However, I was thinking about this whole thing last night and I've come to the conclusion that I'm really not that bothered why the ride height thing works, but I'm bloody glad it does!

Using the ride height setting/bug/glitch/trick/expolit (call it what you will) has completely rekindled my enjoyment of the game. Before this, I'd take a car I fancied driving and spend hours trying (and failing) to get the car to handle how I wanted it too. Everything just understeered horribly, and most required stupid amounts of toe to try and fix this. I wasn't really enjoying the driving experience as I had expected to.

Yesterday, I tried a few cars I had driven previously and not enjoyed. Sticking the front max, rear min ride height on them immediately made them feel so much better to drive. A few other changes to cancel out previously high toe or camber settings and they started to feel wonderful. Now, instead of just plowing on under turn in, they will carve to the apex... they will still understeer if pushed too hard, but that's how it should be.

For whatever reason, the cars 'feel' much more like they should IMO with this setting applied so I will continue to use it and enjoy the game so muhc more as a result

Yeah but it still needs to be fixed, I don't want to drive a car with its nose in the air because its faster/handles better, this is "The real driving simulator" isn't it?

 

[No_OBsT33R]

Preliminary test show adjusting the spring rate to the height offset has eliminated the adverse effect. Providing your springs are balanced to begin with.

Meaning if you raise the rear soften the springs, if you drop the rear stiffen them. Starting from a balanced set.

I'll do further testing, but it's looking like the reversed effect IMO (as not fully tested) is debunked.

Only thing I'm seeing is no under body aero effects whatsoever. Looking like its just a cheap tuning trick for faster acceleration/top speed more and more.

 

[Z1-AV69]

Anyways, hopefully we can now put the top speed stuff behind us and return to the task of trying to figure out if nose-up tuning reduces understeer because
a) the front/rear ride height adjustment is the wrong way around
b) downforce is modelled as a vector perpendicular to the car's surface- this means nose-up is putting more downforce on the front tyres and actually the downforce is accelerating the car forward
c) spring rates are affected by ride height change- 40% higher front height means 40% stiffer front springs (even though the value in the spring adjustment hasn't changed)
d) something else!

Ok, now my test of theory "b":

The car is a Zonda R '09 with engine stage 3 but without high rpm turbo at 637kw/1070kg. Basic setup:

LSD: 7/30/15
Height: 0/0
Springs: 12.0/15.0
Extension: 5/5
Compression: 5/5
Anti-roll: 3/3
Camber 0/0
Toe: 0/0
Brakes: 5/5 (ABS:1)
Gearbox: max speed 420 km/h
Aero: 40/65

on racing softs

The track is Circuit de la Sarthe '09 without chicanes in practice mode. Top speeds are as follows:

1a. 0/0 ride height, 40/65 aero: 362 km/h
1b. 0/0 ride height, 20/35 aero: 377 km/h
1c. 0/0 ride height, 20/65 aero: 371 km/h
1d. 0/0 ride height, 40/35 aero: 366 km/h (difficult to keep the car straight)

2a. +15/-30 ride height, 40/65 aero: 371 km/h
2b. +15/-30 ride height, 20/35 aero: 381 km/h (already touching red rpm)
2c. +15/-30 ride height, 20/65 aero: 379 km/h
2d. +15/-30 ride height, 40/35 aero: 373 km/h (difficult to keep the car straight)

3a. -30/+15 ride height, 40/65 aero: 356 km/h (terrible over bumps, but best handling otherwise)
3b. -30/+15 ride height, 20/35 aero: 373 km/h
3c. -30/+15 ride height, 20/65 aero: 365 km/h
3d. -30/+15 ride height, 40/35 aero: 363 km/h (difficult to keep the car straight)

So the interpretation is a lot more difficult than I thought, because GT5 seems to factor some drag. Additionally the top speeds aren't at the same rpm, I should have used the power limiter.

Yet still I think it proves theory "b", but not as good as I hoped: the difference between 1a and 2a is 9km/h and the difference between 1b and 2b is only 4km/h. So the effect of a +15/-30 ride height increases greatly with more downforce.

But the question remains why the difference between 1a minus 3a and 1b minus 3b is so much smaller. Following theory "b" it would be probable the effect would pull the car back just like it pulls forward in 2 a-d. Now in a real car it needs a lot of power to make it 15km/h faster at those speeds. But this explains only some of the difference imo. The other part could be lower drag with -30/+15 vs. +15/-30, which could support the reverse theory "a". But imo the data from this test is too thin to prove that.

Anyway, after this test I'm quite convinced that the immense quickness of +15/-30 height tunes does not come from better handling, but from downforce pulling forward.

 

[phil_75]

Anyway, after this test I'm quite convinced that the immense quickness of +15/-30 height tunes does not come from better handling, but from downforce pulling forward.

???
But it does handle better! That was the point of this thread in the first place.

Cut all the technical jargon, Car "x" when dropped at rear acts as if front is lowered and vice versa.

 

[Z1-AV69]

Because the 2b test did come too high in rpm, slightly touching the red area, here is another set of tests with 420km/h max speed and power limiter at 80%, resulting in 509kw:

1a. 0/0 ride height, 40/65 aero: 344 km/h
1b. 0/0 ride height, 20/35 aero: 354 km/h

2a. +15/-30 ride height, 40/65 aero: 350 km/h
2b. +15/-30 ride height, 20/35 aero: 357 km/h

So after ironing out that flaw, the result proves my interpretation as the effect of a +15/-30 ride height again is significantly stronger with max downforce. Touching the red didn't hurt in my first test.

But the question remains why the difference between 1a minus 3a and 1b minus 3b is so much smaller. Following theory "b" it would be probable the effect would pull the car back just like it pulls forward in 2 a-d. Now in a real car it needs a lot of power to make it 15km/h faster at those speeds. But this explains only some of the difference imo. The other part could be lower drag with -30/+15 vs. +15/-30, which could support the reverse theory "a". But imo the data from this test is too thin to prove that.

The lower difference at the lower speeds of the second test with power limiter suggests the lower difference between 1a minus 3a and 1b minus 3b can be fully explained by lower speeds and the difference in the power band. No reverse theory needed here.

 

[Z1-AV69]

???
But it does handle better! That was the point of this thread in the first place.

I don't think thats generally true. The above Zonda R handles best with -30/+15, which is inline with my experience with other rear-heavy cars. As already stated I believe a higher ride height does increase suspension travel and does effectively stiffen the springs. On top of that, the lower axis gets an increase in stability.
A +15/-30 ride height can of course make a better handling on some cars with some setups. But thats not generally true. Another aspect could be that most road cars have only adjustable rear downforce. Setting it to max will make bad understeer and +15/-30 can indeed help with that.

But the undoubted quickness comes imo from the downforce effect.

 

[No_OBsT33R]

Seems theory B & C don't exclude each other... That's not a bad thing...

I'm letting more of these test yield results like that (good work) I wouldn't jump to conclusions just yet when interpreting them. On the surface Aero effects are modeled pretty well minus the under car aero effects.

I've already tested and have been finding that adjusting the SR with your ride height offset cancels out the negative effect of the offset.

Still more test need be done. This is great progress.

 

[Z1-AV69]

What's really bad: The above findings basically ruin any competitive tuning as a +15/-30 ride height is required to be quickest...

 

[st1sj]

Z1 thanks for the results. What about min ride height front and back? I would be curious to see your results on that, compared with the other 3 ride heights.

 

[Johnnypenso]

I don't think thats generally true. The above Zonda R handles best with -30/+15, which is inline with my experience with other rear-heavy cars. As already stated I believe a higher ride height does increase suspension travel and does effectively stiffen the springs. On top of that, the lower axis gets an increase in stability.
A +15/-30 ride height can of course make a better handling on some cars with some setups. But thats not generally true. Another aspect could be that most road cars have only adjustable rear downforce. Setting it to max will make bad understeer and +15/-30 can indeed help with that.

But the undoubted quickness comes imo from the downforce effect.

This result from the Zonda R does not disprove the theory that a higher front end gives more grip. If the Zonda normally has oversteer, which I think it does, by lowering the front and raising the rear, you would in theory be moving the car away from over towards understeer making a better balanced car.

 

[Johnnypenso]

What's really bad: The above findings basically ruin any competitive tuning as a +15/-30 ride height is required to be quickest...

I don't believe this to be the case, because there is a lot more to quick lap times than just top speed. Also, there's no guarantee how the car will handle with a +15/-30 setting. Any given car could be fast in a straight line with that set up, but not good on the corners, resulting in slower lap times. The Zonda for example would not corner well with those settings.

 

[Z1-AV69]

What about min ride height front and back? I would be curious to see your results on that, compared with the other 3 ride heights.

With the original car (637kw) from the first set:

1a. 0/0 ride height, 40/65 aero: 362 km/h
4a. -30/-30 ride height, 40/65 aero: 364 km/h
5a. +15/+15 ride height, 40/65 aero: 362 km/h
6a. -25/-25 ride height, 40/65 aero: 363 km/h

Interesting. It seems to start only at quite low heights, between +15 and -15 there is no change at all. Does anyone have a theory for that?

 

[Z1-AV69]

I don't believe this to be the case, because there is a lot more to quick lap times than just top speed. Also, there's no guarantee how the car will handle with a +15/-30 setting. Any given car could be fast in a straight line with that set up, but not good on the corners, resulting in slower lap times. The Zonda for example would not corner well with those settings.

You can use all the other settings to make such a tune handle well, I see no problem in that. Stotty posted a McLaren MP4-12C tune here which has imo flaws but is still a lot quicker than any of the tuner challenge entries. It's not only top speed. The pulling forward by downforce happens all the time. It's an effective power increase unnoticed by the PP system. And it is not even bound to the tyres traction limits.

 

[No_OBsT33R]

This result from the Zonda R does not disprove the theory that a higher front end gives more grip. If the Zonda normally has oversteer, which I think it does, by lowering the front and raising the rear, you would in theory be moving the car away from over towards understeer making a better balanced car.

Why? Higher rear end will transfer more lateral weight in a corner and potentially oversteer not understeer. Lower rear should transfer less weight and potential understeer.

 

[nomis3613]

Z1-AV69, wow great testing, thanks heaps for sharing. I think your second set proved that your first tests were valid, so I'll only comment on your first set of tests.
(btw, ignore phil_75, he has his theory and isn't willing to consider any alternatives)

1a. 0/0 ride height, 40/65 aero: 362 km/h
1b. 0/0 ride height, 20/35 aero: 377 km/h
1c. 0/0 ride height, 20/65 aero: 371 km/h
1d. 0/0 ride height, 40/35 aero: 366 km/h (difficult to keep the car straight)

2a. +15/-30 ride height, 40/65 aero: 371 km/h
2b. +15/-30 ride height, 20/35 aero: 381 km/h (already touching red rpm)
2c. +15/-30 ride height, 20/65 aero: 379 km/h
2d. +15/-30 ride height, 40/35 aero: 373 km/h (difficult to keep the car straight)

3a. -30/+15 ride height, 40/65 aero: 356 km/h (terrible over bumps, but best handling otherwise)
3b. -30/+15 ride height, 20/35 aero: 373 km/h
3c. -30/+15 ride height, 20/65 aero: 365 km/h
3d. -30/+15 ride height, 40/35 aero: 363 km/h (difficult to keep the car straight)

...the difference between 1a and 2a is 9km/h and the difference between 1b and 2b is only 4km/h. So the effect of a +15/-30 ride height increases greatly with more downforce.

Agreed.

So the interpretation is a lot more difficult than I thought, because GT5 seems to factor some drag.
...
Yet still I think it proves theory "b"...

Pesky drag, eh! If max downforce (test 2a) gave higher top speed than min downforce (2b), then the interpretation would be much easier. Still, it's worth noting that nose-up was faster for every downforce combination.

But the question remains why the difference between 1a minus 3a and 1b minus 3b is so much smaller.

Just to clarify, you're wondering why @ max downforce
- nose-up vs flat gives an improvement of 9 km/h (1a - 2a), but
- nose-down vs flat gives a reduction of only 6 km/h (1a - 3a)
Is that the question?
(note @ min downforce the improvement of nose-up is actually the same as the reduction for nose-down)

Following theory "b" it would be probable the effect would pull the car back just like it pulls forward in 2 a-d. Now in a real car it needs a lot of power to make it 15km/h faster at those speeds.

Actually, it's the other way around, the 9 km/h difference is occurring at higher speeds than the 6 km/h difference, so the difference in drag is even greater.

My sketchy theory is that rear grip is being taken into account (yes, even though you're not getting wheelspin at these speeds). Notice that the speed reduction for adding rear downforce is less than for front (even though you are actually adding 30 units compared with 20) for all rake angles. So maybe what's happening is pushing the downforce vector backwards increases the grip to the rear wheels, which partly offsets the downforce pulling the car back.

 

[watermelon punch]

My questions (which I don't feel are clearly explained in the previous posts)...

1. Are people saying the "reverse" is that rear is front & front is rear... or are they saying that up is down & down is up?? Is anyone sure about it? Or no?

2. I tend to find it's helpful to stiffen (move up) the spring rate, as I lower (move down) the ride height. Is this what should work in real life to get better handling?
(Of course this depends on other settings as well, and depends on the car, but I've tended to find this helpful generally as a starting point. And other comments here & elsewhere seem to go with the same general rule.)

.... my comments which may or may not be relevant? ....

There are times that I tinker with the ride height, spring rate, and anti-roll bar settings - the front or rear, in a way that helps me, but that my boyfriend says in real life terms should NOT help the way I say it does.

I have ZIP BUPKIS experience/knowledge about real life tuning. I go SOLELY by my experiences in trial & error tuning in gt5.
My bf knows about real life tuning, etc etc.
Sometimes his methods don't work as well as mine to achieve the same goal... To me that says there's something "off" about gt5. Because if it was 100% realistic, then my bf should always know more than me.

What I'm most interested in, is some kind of testable conclusion about what exactly in tuning, differs greatly from real life tuning.
And if it's isolated or not to certain cars, or certain types of cars. Or certain situations/tracks/goals.
Then I can know what I'm dealing with.

If no one can put their finger directly on it... Then I'm still stuck with just going with the trial & error method. And this topic is kind of moot.

 

[adeadsnipermatt]

You need to test a car with no down force and the add a wing to check 0 down force is fast nose up. But I wanted to say I ran a Veyron 1200hp max front/min rear 271mph. Also 271 mph min front and back so downforce in my test seems to effect the speed alot in some cars.

 

[nomis3613]

Here's some inconclusive testing I've just done, to throw into the mix. I was hoping to see whether Z1-AV69's link between the effect of nose-up and the amount of downforce also applied to front grip in cornering. But...ummm... see for yourself:

Test was at R246 turn 4 (the RH sweeper), cars were set up to understeer heavily, so that cornering speed would be show improvements in front grip. LSDs were 5 / 5 / 5. Downforce was minimum/maximum at both ends as stated, however the Integra wasn't consistently understeering at high speed so I used 5 / 20 as the "minimum" downforce instead.

Integra RM on Sport Hard
height, downforce, cornering speed
0 / 0, minimum, 132 km/h
0 / 0, maximum, 137 km/h
40 / -25, minimum, 134 km/h
40 / -25, maximum, 137 km/h

Zonda R on Racing Hard
0 / 0, minimum, 147 km/h
0 / 0, maximum, 157 km/h
0 / -40, minimum, 160 km/h
0 / -40 maximum, 160 km/h

Zonda R on Racing Soft
(car was quite oversteery for these setups)
0 / -40, minimum, 170 km/h
0 / -40, maximum, 170 km/h


It's interesting that adding aero didn't improve grip in some cases (tyres already maxed out? but that is a discussion for another thread).

Make of it what you will, but I can't see any clues from these results.

 

[phil_75]

I don't believe this to be the case, because there is a lot more to quick lap times than just top speed. Also, there's no guarantee how the car will handle with a +15/-30 setting. Any given car could be fast in a straight line with that set up, but not good on the corners, resulting in slower lap times. The Zonda for example would not corner well with those settings.

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?

 

[Maffski]

Gotta say Chris, this is a fascinating thread with some great incites coming from everyone. 👍

Thing with this glitch/bug is that if hypothetically PD simply reversed the settings so jacking up the rear reduced understeer we would still be in a situation where tuning is totally borked, ie everyone would be running round with the rear jacked up to the rafters which is plainly unrealistic. Surely if Slamming the front and jacking up the rear was a good thing to do in the real world then every race car and performance car would have 70's style rake, but obviously they don't and you have to assume this is because it compromises the handling. One notable exception being the current Redbull F1 car which appears to have a lot of rake.

As much as I hate to say it, this glitch demonstrates that the physics in this game are really quite messed up and they need to go back to the drawing board, which is a real shame as I think the cars feel very good to drive and can only imagine that any fundamental changes to the physics would not improve gameplay. If it came down to it I could ignore the problem and would merrily go on my way with the front jacked up and just enjoy the game for what it is, but I know others will not consider it and would prefer to drive a crippled car than exploit a glitch which in it's own way is rather admirable.

I just hope this glitch has been on PD's radar for some time and that they are working on a fix, but going on their past record I'll not be holding my breath for that.

 

[Z1-AV69]

Just to clarify, you're wondering why @ max downforce
- nose-up vs flat gives an improvement of 9 km/h (1a - 2a), but
- nose-down vs flat gives a reduction of only 6 km/h (1a - 3a)
Is that the question?
(note @ min downforce the improvement of nose-up is actually the same as the reduction for nose-down)Actually, it's the other way around, the 9 km/h difference is occurring at higher speeds than the 6 km/h difference, so the difference in drag is even greater.

With nose down we are looking at downforce pulling the car back while the engine works against that. So a smaller difference means the car does better against the force at those lower speeds. Additionally my second test suggests that the downforce pulling forward or backward is already noticeable weaker at the lower speeds.
But all that is quite complicated because of the steep power band of the Zonda in set 1. I wouldn't interpret too much about that, I just wanted to be sure nose down pulls back like nose up pulls forward and I think it proves that.

My sketchy theory is that rear grip is being taken into account (yes, even though you're not getting wheelspin at these speeds). Notice that the speed reduction for adding rear downforce is less than for front (even though you are actually adding 30 units compared with 20) for all rake angles. So maybe what's happening is pushing the downforce vector backwards increases the grip to the rear wheels, which partly offsets the downforce pulling the car back.

I was curious for your interpretation about front/rear downforce, so thanks for that. But I have doubts about it being more grip on the rear wheels. The speed measurements have all been done at the second chicane where the track is suddenly very even. As you noted there is no noticeable wheelspin and I tend to trust that. My theory would be a difference in the drag associated with more downforce. If front downforce produces more drag than rear, it would explain the difference. Of course both theories sound somewhat weird and I don't know what is right here.

 

[Sm0k3:D]

I'm totally lost right now. In theory a car set to max/min ride height should had a poor grip in the front end while you're accelerating, so it should be almost uncontrollable at exit of a corner. Is this correct? (Maybe i'm wrong)
I don't know what is happening here, can't tell if front/rear values are backward, but i'm sure there's something wrong with the physics in the game...

 

[Stotty]

Surely if Slamming the front and jacking up the rear was a good thing to do in the real world then every race car and performance car would have 70's style rake, but obviously they don't and you have to assume this is because it compromises the handling. One notable exception being the current Redbull F1 car which appears to have a lot of rake.

Maff

It's not really that the cars are 'jacked up' like a drag car... the range of adjustments on the ride height is pretty narrow (assuming they are in mm, as any other measure would be a bit silly!). So on most cars you're talking about no more than a 3" difference front to rear. That's not a big number, though it looks worse in the game as GT tends to over state the adjustment visually.

Just try it... the way the car handles with the ride height set higher at the front feels so much more natural than anything else I've tried. Cars that had unfixable understeer are suddenly nice to drive

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

Regarding this 'downforce pulling the car forward' theory... this is plain rubbish... downforce can't 'pull' the car, it will always hold it back to a greater or lesser degree.

The effect of high front/low rear increasing straight line speed actually backs up the theory that the front/rear settings are transposed. A low front end would mean less air is getting under the front of the car and a lower frontal area... both contributing to less drag and more speed.

 

[Z1-AV69]

Regarding this 'downforce pulling the car forward' theory... this is plain rubbish... downforce can't 'pull' the car, it will always hold it back to a greater or lesser degree.

In real life: for sure. But to get this into the game it would need a complete modeling of the airflow around the car. I'm quite sure GT5 doesn't model this. So the effect of downforce pulling forward is an exploit of the poor modeling.

The effect of high front/low rear increasing straight line speed actually backs up the theory that the front/rear settings are transposed. A low front end would mean less air is getting under the front of the car and a lower frontal area... both contributing to less drag and more speed.

Well I'm no aero-engineer. Does it really matter for drag if the air goes under or over the car (it matters for downforce of course)? The test with min ride height is important here as the air under the car is roughly the same as nose down but still the speed difference is much smaller.

Doesn't any rake being positive or negative increase the overall frontal area? At least if we assume drag is optimized for a 0/0 height? Additionally nose down would steepen any wings on a real car, resulting in more drag from the wings. Nose up would be the other way around. This is especially important since the aero adjustment likely only changes the angle of any wings.

As said, I'm not Adrian Newey, but I don't think differences in drag can explain the speed difference.

 

[budious]

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?

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 perpendicular to the angle of gravity (the horizontal plane of the course map, the surface you drive on when money glitching).

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?

 

[Z1-AV69]

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?

There would still be drag, I don't think the results would be more telling.

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 perpendicular to the angle of gravity (the horizontal plane of the course map, the surface you drive on when money glitching).

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?

I agree. Such a test would be useful if done with a car with even weight distribution.

 

[budious]

There would still be drag, I don't think the results would be more telling.

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

I agree. Such a test would be useful if done with a car with even weight distribution.

Weight distribution shouldn't be too much of a problem because rate of free fall is independent of weight, if physics adhere to expected behavior profile. The control test with no aero at front or rear should setup the control angle. Then you can measure changes in angle and distance from crest to surface contact changes with various aero settings applied.

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.