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View Full Version : A test I'd like some of you to do to confirm something



Redslayer
01-02-2016, 01:38
It appears to me, and the people I race with, that setting your camber to 0 front and back, makes no negative difference, and gives better straight line speed (be it just from acceleration or whatever). I ran several laps with normal camber settings, then put them on 0, and noticed no ill effects, and my lap times remained similar.


Now, to be fair, I haven't yet tested this thoroughly on a track I can be super consistent at, but my friends assure me that it doesn't hurt. And considering I recently won a league race running 0/0 camber, they seem to be right. It's possible I just got lucky, because the rain came, and I am better in the rain than most of the people I race with. But I still feel like it should be slowing me way down.

SGETI
01-02-2016, 22:25
have a quick read. This camber issues as been discussed numerous times. If you use the search feature you will find many threads and hours of reading. Example from Jussi Karjalainen


I also managed to isolate the slight camber thrust effect that we get from running high camber: YES, high camber DOES provide a lateral effect. It is a very small effect though.

I tested it by driving down the drag strip on the Test Track. With both minimum and maximum camber on all corners, the car tracked on completely straight, I could let go of the wheel and the car held the line perfectly. Then I tried running maximum camber on the left side and minimum on the right side, so -4.5 front and -3.5 rear on the left, and 0.0 front and rear on the right. This time I had to constantly keep a slight leftward pressure on the wheel to keep the car straight, if I let go the car veered to the right. This proves that there is a camber thrust effect from camber as there should be, though I do readily admit that the effect is more than likely smaller than it should be.

We already know that cars currently tend to get much lower rolling resistance with minimal camber settings than they do with high camber settings, meaning camber causes increased rolling resistance (something the devs have noticed and are fixing currently*). This is realistic based on the test data I've found, a German study made specifically on this subject, depending on the combination of camber and toe angles used, but the effect seems to be too high currently, it should mostly balance out in reality. However if the only thing the camber was doing was adding drag, then it would also have made the car veer to the left, since the left side tyres were the ones with high camber. So the camber thrust effect is at least strong enough to beat the increased drag from extra camber and still push the car slightly to one side.

The effect is likely smaller than it should be though, based on discussions with the devs during development and reading up on racing car dynamics the effects of camber thrust tend to be so good that you still get significant cornering benefits even when you're actually beyond the point where you have maximum contact patch, the main drawback being sharply increasing tyre wear with extreme camber settings. In more endurance oriented races I've seen mentions of running cambers in the -2 to -3 degree range, but in sprint racing things can be very different. Michelin for example recommended Porsce Supercup teams to run -4.5 degrees of camber front and rear as a starting point, and that the temperature differential between inside and outside of the tyre should be around 20 degrees Celsius (whereas many people often tout the 5 degree celsius rule).

So camber IS working, it's just not balanced correctly. It doesn't give enough in corners and takes away too much on straights.

*Worth noting is that this is NOT a fundamental issue of the tyre model, just a balancing issue. There was a time when maximum camber gave you so much cornering grip it was the only setting worth running. It's clearly hard to balance this with a dynamic physical tyre model, when you don't have a simple "camber sensivity" parameter at your disposal.

Redslayer
04-02-2016, 23:33
have a quick read. This camber issues as been discussed numerous times. If you use the search feature you will find many threads and hours of reading. Example from Jussi Karjalainen

I actually tried to search and it was full of unrelated crap. I unfortunately don't have tons of time to waste sorting through a forum. So thanks.

flatspunout
05-02-2016, 06:00
Sonoma GP, Ruf GT3, Real Assists

Ran 10 laps with -3.0F and -2.5R, best 4 laps were 1:31.200 1:31.048 1:31.294 1:31.040. Inside edge of tires 1-2 degrees hotter than outside. Changed camber to minimum -.09F and 0.0R, best 4 laps were 1:31.330 1:31.302 1:30.759 1:30.931. Outside edge of tires 1-2 degrees hotter than inside.

Honestly the car didn't drive much differently either way... maybe a tiny bit less responsive with minimum camber. Fastest lap was with minimum camber, I'm shocked considering even the straightaway isn't straight at Sonoma.

Redslayer
05-02-2016, 17:00
Sonoma GP, Ruf GT3, Real Assists

Ran 10 laps with -3.0F and -2.5R, best 4 laps were 1:31.200 1:31.048 1:31.294 1:31.040. Inside edge of tires 1-2 degrees hotter than outside. Changed camber to minimum -.09F and 0.0R, best 4 laps were 1:31.330 1:31.302 1:30.759 1:30.931. Outside edge of tires 1-2 degrees hotter than inside.

Honestly the car didn't drive much differently either way... maybe a tiny bit less responsive with minimum camber. Fastest lap was with minimum camber, I'm shocked considering even the straightaway isn't straight at Sonoma.

Lol, that's true about the straights. And an interesting result. Guess it's safe to say between that and what the other guy posted, that I'll be running 0.0 camber. I guess it's partially a good thing, since I don't have enough time to delve into tuning.

biggbaddwolf
05-02-2016, 17:23
I don't play this game much anymore, but I just use default set ups. I personally think all the set up things are hoaxy, and really don't affect much, just settings for everyone to play with to make players think they have the ultimate set ups over anyone else.!! JMO

Stevesixty7
05-02-2016, 18:30
I don't play this game much anymore, but I just use default set ups. I personally think all the set up things are hoaxy, and really don't affect much, just settings for everyone to play with to make players think they have the ultimate set ups over anyone else.!! JMO
Altering the set up definitely changes the way a car drives and handles, to suggest otherwise just isn't true. Go and take any car of your choice with default setting, drive a few laps then make dramatic changes (dramatic changes to prove a point) and come back and tell me your lap times aren't different one way or the other, or that the car has become undriveable for instance.

Redslayer
05-02-2016, 20:28
Altering the set up definitely changes the way a car drives and handles, to suggest otherwise just isn't true. Go and take any car of your choice with default setting, drive a few laps then make dramatic changes (dramatic changes to prove a point) and come back and tell me your lap times aren't different one way or the other, or that the car has become undriveable for instance.

Yeah they definitely work. I always tweak cars a little. But all I ever really need is accel/decel diff setting tweaks, front/rear weight balance, downforce and brake balance. Very rare that I need anything else. Because I just need the car comfortable to my driving style. Now I drop camber to 0.0 as well.

If a car REALLY sucks, I start messing with spring rates. But usually only if I'm having excessive oversteer problems.

Stevesixty7
05-02-2016, 20:47
Yeah they definitely work. I always tweak cars a little. But all I ever really need is accel/decel diff setting tweaks, front/rear weight balance, downforce and brake balance. Very rare that I need anything else. Because I just need the car comfortable to my driving style. Now I drop camber to 0.0 as well.

If a car REALLY sucks, I start messing with spring rates. But usually only if I'm having excessive oversteer problems.

I happen to hate understeer and always work the set up to dial it out as much as I can. I think I'll start changing camber now too ;)

Redslayer
06-02-2016, 20:39
I happen to hate understeer and always work the set up to dial it out as much as I can. I think I'll start changing camber now too ;)

I also hate understeer. But if you cant turn the car without the rear tires breaking lose, it's a problem lol. All my tweaks go towards loosening the car to the right degree. But some cars have horrid oversteer on entry that can't be solved without more in depth tuning.

For me, its trying to find that balance where the car is equally loose on or off throttle.

hkraft300
07-02-2016, 02:44
Controversy!
Camber exploit was said to be fixed in patch 7 :rolleyes:
Though that difference in lap times above: could it be just getting more familiar with the car and track?
I've never used zero/minimum camber myself because it doesn't feel stable to drive. My lap times suffered.
Zero camber will theoretically give you better braking and acceleration but suffer a little in cornering and tyre wear too, possibly?
Not sure where I read it but a lot of endurances cars run as little camber as they can get away with. GT3 and LMP cars definitely fall into that category. Then you have sprint-ish racers like touring cars getting all #cambergang on you.

Every setup change will affect your lap times, either 1-lap or average over 50.

Redslayer
08-02-2016, 15:11
Controversy!
Camber exploit was said to be fixed in patch 7 :rolleyes:
Though that difference in lap times above: could it be just getting more familiar with the car and track?
I've never used zero/minimum camber myself because it doesn't feel stable to drive. My lap times suffered.
Zero camber will theoretically give you better braking and acceleration but suffer a little in cornering and tyre wear too, possibly?
Not sure where I read it but a lot of endurances cars run as little camber as they can get away with. GT3 and LMP cars definitely fall into that category. Then you have sprint-ish racers like touring cars getting all #cambergang on you.

Every setup change will affect your lap times, either 1-lap or average over 50.

It doesn't seem to make as much difference as it should imo. Even if it is supposedly fixed.

hkraft300
08-02-2016, 15:49
It doesn't seem to make as much difference as it should imo. Even if it is supposedly fixed.

The straight line speed advantage was fixed by way of rolling resistance adjustments to the tyre model, iirc.
Camber effects will depend on the car itself. I'm no expert and haven't done any testing beyong setup and wear rates on some cars.
Tyre model development for pcars1 is over though, so no more changes to be expected for this title.

Sir Digby Chicken Caesar
08-02-2016, 23:33
Yeah, they fixed the speed part, but handling realism and camber is still very suspicious. Basically the car is more nimble with lots of neg. camber when not cornering hard, but there's no benefit when cornering hard.

hkraft300
09-02-2016, 04:02
I get more stablility and consistent times with extra .5 neg camber here and there if I need it. It has a noticeable effect on tyre wear too.
Jussi did a simple test of camber thrust effect and found it minimal but present.
So, yes, in hard cornering the benefits are minimal, therefore minimum camber is better in the tyre wear and braking/exit sense.