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ELAhrairah
02-06-2015, 18:21
In dunlop curves, mulsanne and indianapolis/arnage rear breaks away when exiting..any idea what can help ?:acne:

Jynn
02-06-2015, 23:02
In dunlop curves, mulsanne and indianapolis/arnage rear breaks away when exiting..any idea what can help ?:acne:

I've struggled with this a lot too in many cars. After doing lots of spring and damper changes with no good effect, I eventually found a very simple solution, just move the brake bias forward a bit. Hmm actually that's more of a corner entry thing, try softening the rear springs and/or changing the diff.

Umer Ahmad
02-06-2015, 23:11
Need more info

On/off throttle?
Braking/coasting?
Corner entry/mid/exit ?
Kerb or track?

edit: lol "when exiting", sorry. Reduce (slide left) ACCEL diff lock

hkraft300
02-06-2015, 23:27
It's not just power that overwhelms traction at the rear wheels, its torque.

The R18 has >1100Nm of torque from its turbo diesel engine from very low rpm, which is nearly double EVERY other car in this game. It's nearly double the other LMP1 cars but the tire width/contact patch is the same.

So what's happening is - you sneeze on corner exit = power oversteer
you hold your breath through the corner and exhale as you exit = power oversteer
you hold your breath longer through the exit but your heart beats = power oversteer
daddy mouse in your wall starts to feel a little randy and gets all up on mommy mouse = power oversteer....

but don't be shy with it. The R18 likes it rough. Just make sure you've straightened up before you get on the gas :)

Reduce accel diff lock ^ what Umer said
try a gear higher than you normally would. Use the turbo diesel torque.

FMS TopSecret
03-06-2015, 13:54
With Indianapolis its not a torque issue, on the mulsanne straight the car bottoms out a lot. so when going through Indi it bottoms out and then spins out into the right barrier, you have to take the corner a lot slower than the other LMP cars losing precious time. also i think the accel on the r18 is 0% stock if im correct?

ELAhrairah
03-06-2015, 22:55
thx guys ..I will take this advise and try it out :o:yes:

hkraft300
04-06-2015, 12:02
With Indianapolis its not a torque issue, on the mulsanne straight the car bottoms out a lot. so when going through Indi it bottoms out and then spins out into the right barrier, you have to take the corner a lot slower than the other LMP cars losing precious time. also i think the accel on the r18 is 0% stock if im correct?

spot on about the diff mate.

indi is still a turn I take wide-ish. I don't run bump stops because I live the low life lol
increase ride height, stiffer springs - helped me tame the RWD P30 on Bathurst and other bumpy tracks but the R18 was still doing my head in. maybe try the stiffer springs to minimise scraping?

xxBENxx
04-06-2015, 12:14
In dunlop curves, mulsanne and indianapolis/arnage rear breaks away when exiting..any idea what can help ?:acne:

Try increasing the rear spring rate and also reduce the rear ride height.

MULTIVITZ
04-06-2015, 21:26
Yeah its got a massive diffuser. But don't lower too far or it will understeer I think. Soft springs, medium height, correct rebound and a bit of toe slider to the right a bit in the settings. I had it with stiff arbs and it practically sat on its bumpstops! Felt good though. Make sure the tyres are pumped up enough, you'll feel it lurch to one side before it breaks away a bit like low camber does when you go on the limit and not too much camber. I had a little play last week but haven't had time to test it. Just remembered its got really good anti squat so heavy springs will upset it! Such a stable car that R18, I could fall asleep at the wheel lol.
At the end of the day its up to you. Just respect the wedge and mid cornering will be a joy.

tankyx
05-06-2015, 12:04
The setup isn't the problem, it is your throtteling :) You should be more precise. I drive the R18 with 0 - 0 downforce, and I don't experiment any oversteer (3'25 my best time on le Mans, pretty average I guess)

MULTIVITZ
05-06-2015, 12:24
Thats a good way to tune mechanical grip (using minimal wing) but bare in mind these cars have quite alot of residual downforce. My downforce post explains it's effects and problems. Even just sligh aero can interfere with springing when driving on the limit. These cars also have suspension that reduces the detrimental effects through clever geometric designs and damping characteristics.

charliev69
09-06-2015, 09:55
It sounds like the R18 is one of the hardest cars to setup for LeMans , by default it is very loose through the slow corners , the front seems to lack grip and doesnt inspire confidence to push on , this coupled with the tendency for the rear to break away under acceleration makes it a real challenge. Le Mans is bumpy in places and the car needs some suspension adjustments to iron out the bouncing I think.
My initial thoughts where to soften the front ARB and add some accel diff lock , and maybe a click more caster ?
But I need some expert advice for the springs and dampers .

hkraft300
10-06-2015, 00:23
I find it hard to feel caster effects through the controller yet
the spring and damper rates are pretty high at default I think, compared to other cars. maybe test them low and high see how it feels.

accel diff lock may help but a high rate makes power oversteer too abrupt for my controller settings - I'm mostly between the 15-30% range in other cars (LMP and open wheel).

maybe soft front arb with stiff springs and slow bump for good response and low fast bump for the rough road? It worked for me with the RWD P30 at Bathurst but not R18