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cjhill44
18-11-2017, 23:08
Hi guys

I was doing a race at Le Mans (de la sarthe) using LMP1/LMP2/GTE classes. 1 hour race with driver swaps

I was driving the 2014 AUDI R18 E-TRON QUATTRO.

My top speed down the Mulsanne straight after the exit from the flat out 'Terte Rouge' was 180mph, the car would top out at this about halfway down the straight, apart from when i was in another cars slipstream when it would be up to 187mph.

However when I switched at a pitstop my co driver was able to reach 189mph with NO draft and 195mph in the draft. I know these cars have ERS but like in F1 the driver has no control as to when to use this and this is not getting deployed on exit of Terte Rouge.

So how does he have more top speed than me?

hkraft300
18-11-2017, 23:18
Well, you'll probably eek out a few extra mph yourself if you don't set the final drive at the minimum value.

AI cars are on a "simple physics" model, so their setup, tires etc are different. So don't judge by AI performance.

sp3ctor
19-11-2017, 00:07
Right, but what he is saying is same car, same set up with an AI driving a stint, the AI is making 2-6mph more flat in a straight... I can understand saying not to compare your driving to an AI competitor, particularly in overall times, but if car X goes Y flat out in a straight and you swap to the AI driver, it really shouldn’t be able to go any faster than Y because there’s literally no skill, setup or car differential flat out in a straight. Interesting.

Shogun613
19-11-2017, 00:07
Carrying as much speed as you can through Tertre Rouge and maximising your exit speed is key. Don't brake for the kink, just lift early enough to toss it in and not go too wide on the exit strips. Then stay tight to the right through the second kink to avoid the bumps on the left as it opens up to the Mulsanne.
With my PCars1 setup I was able to hit 202 before braking hard for the chicane.

WvAllwheelDrive
19-11-2017, 00:15
Also save hybrid power after going though Dunlop until after going through Tertre Rouge. You can get the R18 to about 205 before running out of hybrid and aero slowing the car, the TS040 can hit about 210.

z3r0cool77
19-11-2017, 00:21
Ai are also on different tire model. Maybe try upping tire pressures to reduce rolling resistance. Shouldnt make a lot of difference but might help.

Also, how do you know ai are using the same downforce? Does that car have adjustable downforce anyway? I dont honestly know and cant check atm.

I also wonder that since ai are on a simplified physics model to they just always get slipstream effect regardless of whether or not they are behind another car? I think its possible.

hkraft300
19-11-2017, 00:31
Right, but what he is saying is same car, same set up with an AI driving a stint, the AI is making 2-6mph more flat in a straight....

Ye but...



AI cars are on a "simple physics" model, so their setup, tires etc are different. So don't judge by AI performance.

And this includes your AI Co-driver, I believe.
Also:


Ai are also on different tire model. Maybe try upping tire pressures to reduce rolling resistance. Shouldnt make a lot of difference but might help.

Ringley did suggest ~1.9 bar to reduce some rolling resistance at fast tracks without too big a hit on grip.

Rake and ground clearance are also critical.

Ofnir4
19-11-2017, 10:46
Well, the AI is on steroid, your copilot is on steroid with YOUR setup, so expect him to beat everyone.
Last time the AI drove my TS040 at Le Mans (AI at 90), he beat my time by 2 seconds on normal fuel, reach 330kph on every straights to put a 3:18.

Other than that, reaching top speed halfway down the straights is bad gearing, taking Tertre Rouge flat out is either too much downforce or unoptimized hybrid recovery. Saving energy from the dunlop curves and tertre rouge is better for your laptimes.

cjhill44
19-11-2017, 13:21
Carrying as much speed as you can through Tertre Rouge and maximising your exit speed is key. Don't brake for the kink, just lift early enough to toss it in and not go too wide on the exit strips. Then stay tight to the right through the second kink to avoid the bumps on the left as it opens up to the Mulsanne.
With my PCars1 setup I was able to hit 202 before braking hard for the chicane.

Yeah,that's exactly what I do, I feel like I have a pretty good line through there, and even if i didnt, I would still reach the higher speed, it would just take longer.


Also save hybrid power after going though Dunlop until after going through Tertre Rouge. You can get the R18 to about 205 before running out of hybrid and aero slowing the car, the TS040 can hit about 210.

You cannot choose when to deploy ERS, it is done automatically and I'm pretty sure its already being deployed on the straight anyway

I'll just have to try gearing, tyre pressures and ride height but pretty sure it wont gain me the 10mph I'm missing. I just started with the stable setup FYI.

TexasTyme214
19-11-2017, 13:33
Yeah,that's exactly what I do, I feel like I have a pretty good line through there, and even if i didnt, I would still reach the higher speed, it would just take longer.



You cannot choose when to deploy ERS, it is done automatically and I'm pretty sure its already being deployed on the straight anyway

I'll just have to try gearing, tyre pressures and ride height but pretty sure it wont gain me the 10mph I'm missing. I just started with the stable setup FYI.

You can control ERS by limiting the throttle. Around 80% throttle prevents the ERS from turning on. I always save ERS between the Dunlop Esses and Tertre Rouge. It's much faster to do that.

belaki
20-11-2017, 13:08
The simple fact is you won't hit top possible speed for your car unless you configure the car, and therein lies the obstacle for most. The default setups will not do the trick. In the process of learning what's a quick setup, as opposed to a fast set-up, you'll go through a phase where you will be much faster down Mulsanne than the AI but they will still be logging faster lap times.

When you reach that phase is when you'll start to ask the right questions about the difference between quick and fast. To me, this is what the game has always been about.

Finally, not intending to be argumentative, but I can conclusively state that the AI co-driver most definitely *did not* use your setup in PC1. I don't think this has changed in PC2, but I've been spending a lot of time in testing rather than racing (endurance), so I could be wrong about the situation in PC2. I am happy to be corrected if anyone has observed AI co-driver behavior in PC2 that indicates otherwise.