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CastrolGT
14-06-2018, 16:58
hi guys

I have a huge oversteer problem.
The Ford GT on Le Mans is a real mess. I don't understand. no matter what I change in the setup, the car still oversteers when I brake, lift, and on high speed like in the Porsche curves. and when I spin, the car gets on its side wheels like if the center of gravity is too high(literrally, I'm sliding on 2 wheels)

here's the setup:

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I can manage a 3:55 per lap, but I have to fight the car to avoid the oversteer; it really gets irritating and I'm sure that's not how the car drives IRL(I didn't mean that I know how the car drives IRL, but I really suppose it)

AbeWoz
14-06-2018, 17:20
increase your preload on your differential from 30 to like 80-100. also up your power ramp from 55 to about 75 and see how that goes?
you might need to run more aero than the other GTE cars so try 2 or 3 on the rear wing.

CastrolGT
14-06-2018, 17:23
ok. I'll try that. but the Ford GT LM is already slower than it real life counterpart(2016) so, it annoys me a bit to put more rear wing. plus, it gets understeery. but I'll try

EDIT: that did the main trick. but at indianapolis, the right hander, I still get a sudden oversteer even if I brake sooner

EDIT 2: corrected to right hander instead of left hander

rich1e I
14-06-2018, 21:38
Try increasing front ride height a bit. Le Mans is pretty bumpy so we need to raise the ride height anyways. Also I noticed your rear anti-roll bars are pretty stiff. Try 30 maybe. Also, try increasing engine braking to maybe 4 or 5. Maybe a bit more camber as well, front&rear. Remove bump stops and see how it handles, but hey, if you have to fight the car and are still getting 3:55s I wouldn't be too concerned ^^ I run less front anti-roll bars and I don't get all that oversteer.

Edit: I run 65/80 ride height, camber 2.6 /2.3, engine braking 5, anti-roll bars 110/30 and no bump stops. Diff settings 120 preload, 55/35

CastrolGT
14-06-2018, 21:44
the thing is, it's really dangerous at Indianapolis. the car gets sideways on the right hander. even more when I brake. I tried with more camber, nothing. I've put bump stops because the rear scraped the road there. I'll try with less rear ARB again, but that won't do much, as I already tried that

rich1e I
14-06-2018, 22:08
Just noticed also the suspension could be too stiff. On bumpy tracks like Le Mans or Nordschleife teams run softer setups. Try springs 158/123 and see if it's any better

CastrolGT
14-06-2018, 22:11
thanks. I'll see that later

hkraft300
15-06-2018, 01:14
Reduce your bump stop.
You’re probably bouncing off them and into the wall. I run 0-5mm in GT cars.
Also I’d increase rear spring. Try 158/158 front/rear.

Your compression damping is much higher than rebound. Try the opposite: higher rebound than compression. It’ll help settle the car.

rich1e I
15-06-2018, 13:08
Reduce your bump stop.
You’re probably bouncing off them and into the wall. I run 0-5mm in GT cars.
Also I’d increase rear spring. Try 158/158 front/rear.

Your compression damping is much higher than rebound. Try the opposite: higher rebound than compression. It’ll help settle the car.

The problem is, if you want to reduce ridiculous oversteer increasing rear springs doesn't really help. Aero is a good point. He should try 0/2 and he should be fine. My guess is he wants the ultimate straight line speed with very little camber and aero. The thing is, being 3 or 4 kph faster on the straight doesn't help if you lose 1 or 2 seconds in the Porsche curves. Indianapolis, very tricky. I'm also running 0/1 and the car is very unstable through that section so I'm definitely going for 0/2. More aero also helps with braking and overall stability is better.

What also happens very often is that people change too many things, that makes it really difficult to tell what made the car handle so badly at some point. In those cases the best thing to do is back to default and start a new setup.

AbeWoz
15-06-2018, 13:31
your car is setup crazyyyyyy stiff....you have it setup almost like a LMP car.
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Try the below settings:
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Zaskarspants
15-06-2018, 13:44
^^^ This is why I leave all these suspension adjustments at default. If you are not an expert use default loose as it works fine everywhere except at the limit.

The engineer is good too for basic stuff.

CastrolGT
15-06-2018, 15:39
your car is setup crazyyyyyy stiff....you have it setup almost like a LMP car.
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Try the below settings:
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I did a baseline with the suspension calculator provided here. but, I can't afford the PC2 tuner atm. so, I did try to set the car step by step. I guess that I've gone too far because of Indianapolis and his atrocious right hander. I'm actually at 0-2 for the wings, but that doesn't help. I'll try with those springs and damper settings and I'll keep you up to date

CastrolGT
15-06-2018, 16:04
update: the car is now tamed at Indianapolis. but it still oversteers in the Porsche curves. I'll fiddle with the diff settings, maybe that's the problem

AbeWoz
15-06-2018, 16:14
update: the car is now tamed at Indianapolis. but it still oversteers in the Porsche curves. I'll fiddle with the diff settings, maybe that's the problem

lower the rear springs one click

VelvetTorpedo
15-06-2018, 16:20
i was thinking lower the rear sway by one click, but i guess it depends on which part of the curves it breaks loose

CastrolGT
15-06-2018, 17:10
i was thinking lower the rear sway by one click, but i guess it depends on which part of the curves it breaks loose

well, it breaks right in the middle of the curves. full throttle. mostly after changing directions, but also in the real Porsche curve(the climbing right hander just before the double left "Virage du Pont") and in the Maison Blanche curve(the curve just before the fast right-left) all right in the middle. throttle or not. my rear wing is at 2 and it is already slightly understeering on most of the track

EDIT: thanks to Abewoz, the car doesn't have a snap oversteer anymore. I really need to get PC2 tuner. and try to understand more about setups lol

Chawabax
18-06-2018, 19:29
Thank you guys !

Following your advices I was able to move from 3.55 to 3.53 in Le Mans.... working on 3.52 ;)