Race Tire Dynamics 101, Help me understand camber for slicks... Options

[nine14cats]

We've had these type of threads a few times...so here is a recap from our collective personal experiences:

Driver Make Fr/RR Camber
------- ------- -----------------
John Rogers Goodyear ~0/0.25
Racer Chris Hoosier ~0.7-0.9
Brad Goodyear ~0/0.25
Roger Kraus Goodyear ~1.0/1.5
Bill Pickering Hoosier ~1.5/2.0

I tire tested this year both Hoosiers and Goodyears doing auto-x's, TT's and open test days. What I found was that with my driving style, the car was faster with a more camber using Hoosier slicks and the Goodyear slicks licked a little less.

Is this due to tire construction? i.e. the sidewall is stiffer in a Goodyear than a Hoosier?

The reason I ask is that I'm looking at different combinations for next year. I like my 15x7 rim / 23x9.5x15 cantilever slick setup for Auto-X. Combined with my 901 that has been re-geared, I have a very competitive setup.

For Track Events I have a few choices. I can run the same tire/wheel combo as auto-x's or I can run Dot-R's any size. However the camber issues switching between the 2 types of tires makes it a pain.

I was talking to Roger Kraus and he also carries Dunlop slicks in 18" sizes and there are Pirelli slicks in 18" sizes as well. I have a spare set of 18" rims that came off of my 911 I just sold, so I could do more tire testing. The taller tires (~25.2" versus 23") would help on the big tracks I believe. What is interesting about the 18" slicks is that they like between 1.5 and 3 degrees of camber.

That's why I'm interested in understanding the dynamics of the camber settings....I've got alot of options and I plan on tire testing this winter to prepare for next season.

Anyone's comments or experience would be appreciated!

Thanks,

Bill