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      10-08-2013, 10:47 AM   #1
3002 tii
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Why Does Optimal Camber Vary for R-Comps?

So after 30 or so track days I think I'm finally ready to move up to R-comps. In those 30 days I started with Hankook V12's, then Star Spec Z1 and lastly RS3's. I was actually thinking of going back to Star Specs (Z2) but after 'talking' to some folks on bf.c, I think R888's might be a good first R-comp tire. With that said, I've been reading up on different R-comps and what their optimal temp, air pressure and camber settings are.

My question is, why do different tires have different optimal camber settings? For exmple, I was ready to dial in more camber on my car (currently running -2.8*) but read the R888's work best between -2.5 and 3.0* so I'm thinking maybe I should keep my settings as is.
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      10-08-2013, 11:59 AM   #2
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Simple for now, sidewall construction varies from tire to tire
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      10-08-2013, 02:51 PM   #3
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WHS. Camber settings that you read about are related to the tire sidewall. That being said, there are other factors that affect it:

-car weight, as well as where the weight is. On top makes the car roll more.
-suspension (most related to spring rates or sway bars)
-how talented of a driver you are. The fast guys get more grip out of the same tire.
-Etc.

At the end of the day, use the info as a starting point and make changes from there.
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      10-09-2013, 01:02 PM   #4
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I run my R888s at 3.5 negative front camber with good results. The challenge with the R888 is hot tire pressure. I start them out cold at 36 psi front and 34 psi rear with the goal of achieving hot pressures of 45 psi front and 43 psi rear.
My experience is that with lower hot pressures the R888 tends to scrub off the outside edge of the tread rather than wearing evenly. Tire adhesion does not seem to be impacted by tire pressure because the R888 has a very stiff sidewall.
YMMV
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      10-14-2013, 10:23 PM   #5
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How are you getting the R comps to the track? Driving them or build a trailer?

You doing the PCA last weekend of Nov at NJMP?
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      10-14-2013, 10:28 PM   #6
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Quote:
Originally Posted by sipman View Post
How are you getting the R comps to the track? Driving them or build a trailer?

You doing the PCA last weekend of Nov at NJMP?
I'll be there 11/2-3 with Schattenbaum.

Driving to/from track, will follow forecast and if any chance of rain I'll stick to star specs. But I don't plan on running my r-comps till 2014.
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      10-14-2013, 10:30 PM   #7
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Cool. I'll be there too. I'll say hi.
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