DB2-R81

"One trick I did when I ran stock class was to shave the tires at an angle. That would put the thread down properly when the wheel gets positive in a corner."

Does any one running in a stock class use this trick?

typer_801

I don't see much if any gain in doing this. We've got a double wishbone suspension, so we gain camber as we turn unlike many other cars. Also the increased tread height on the outside edge will cause more squirm IMO, than the benefit it adds for additional camber. I've never heard of anyone else doing this either. Also keep in mind, even with my ITR and oversized 225/50/15's on 6in wide wheels, I still get even heat distribution and tire wear on my Kumho's which leads me to believe the car is setup and working properly. In other words, I don't need to find a .05 degrees of camber by shaving my tires unevenly. Of which, I'll never be able to discern the difference.

Just my $.02

johng

I read a article on this. I'll try to find it and post it here.

Hracer

I don't shave my (autox) tires because I want to have as much tread as I can get so they last longer!

DB2-R81

Hey typer_801,

Ether you are not stock or you have one rare ITR. Every stock ITR driver that I have ever spoken with could always use more camber up front. -2.5 to -3.0 degrees seems to be the optimum set-up for the front on Kumho's. Unless you bent something your car didn’t’ come stock this way. The tip came from a multi national champion A MOD car driver/builder who still owns the world’s fastest A MOD autocross vehicle. Even with the countries brightest minds in Formula SAE competing against him, he has stayed way ahead of the pack. If every one did it, it wouldn't be much of a tip. Also it seemed to work for BFG R1's for years. Here is a picture of his car in hill climb trim minus its upper wings. I’m sure this single tip did not bring him his multiple championships but it helped out.



[Modified by DB1-R81, 8:44 PM 8/27/2001]

00R101

I also get very even wear on my tires on my ITR in GS. But I do get some wear on the outside shoulders that more camber would help.

typer_801

As soon as you said A-MOD we began comparing apples and oranges. Those cars do not use DOT Competition tires and anything they do (tire wise) is not comparable to what a stock class competitor would do.

And yes, my car is stock and legal. .8 and .9 (L&R) degrees of camber in the front with the car unloaded. I never said I wouldn't like more camber up front, but getting it via tire shaving is not the hot setup in any stock class, trust me. As I stated before I get even heat distribution and almost even wear across my Kuhmo's with stock sized wheels, oversized tires, and even stock shocks.

You mentioned the the BFG R1's. Remember we don't have those tires anymore. They had camber built into into them (around 1-2 degress I believe) which helped them in that regard. Also note the tread pattern of the R1's basically had a single tread block on the outside half of the tire. In this case it would be possible to shave the tire the way you suggested and potentially get better results. See pic below for clarification.



Having said that, in today's world the R1's no longer exist, so we're forced to use Kumho's, Hoosier's, g-Force R1's, Toyo RA-1's, etc. On all of those tires the tread pattern has tread blocks on the outer edge of the tire and if you were to leave them unshaved (or shave them as you suggested) the tire would squirm considerably and be much slower than a comparable (evenly) shaved tired. For confirmation on this read the tire comparision article in GRM (last month) were they took a shaved and unshaved Toyo RA-1, along with the Kumho and Hoosier tires. They ended up throwing out the unshaved RA-1 because is was soooo much slower than the rest of the tires, even it's shaved brother. Leaving a lot of tread on the outer edge of a DOT competion tire with today's tire choices will most assuredly make you slower.

Todd00

3 degrees of negative camber on an R with slicks is hard to get, because you are forced to run 15" wheels and larger tires. I only have 1.5 degrees or so because if I go any lower, the tire will rub my fender liner (with 225/50's).

And I know it sounds weird, but shaved tires often last longer than unnshaved tires on autox surfaces. If I ran STS, I'd for sure get my street tires shaved.

DB2-R81

Typer_801,

Reread the tip again!

"One trick I did when I ran stock class was to shave the tires at an angle. That would put the thread down properly when the wheel gets positive in a corner."

There was never any suggestion or comparison the technique be used in A/MOD. Only that it came from a very experienced and successful present A/MOD driver/builder with a past history of championships in stock classes and A/MOD.

And it was never suggested that the outer surface of the tire be left at full tread depth. I certainly agree you would end up with a non-competitive tire if you did.

And I would not trust any one who tries to tell me they get even temps and tire ware with Kumho's at -0.9 degrees of static camber on an ITR!


[Modified by DB1-R81, 10:20 PM 8/28/2001]

00R101

DB1-R81 -

You know Jeff (Typer_801) knows his sh*t look at his results Nationally. Where are yours? Bench racing is fine, but when the rubber meets the road Jeff's opinion has far more credibility then yours. Also don't you think its a bit rude to call someone you don't know a liar twice in the same thread?

I think what you are trying to do is shave the inside more than the outside. A good concept proven out by old BFG R-1 but there is a huge problem with your logic. Since the Kumho has a relatively soft sidewall the added pressure on the outside of the tire is only going to exascerbate its already prevalent rollover problem. The shaving concept would probably work better on the stiffer Hoosier Radial but there ain't nothin' to shave.

Overall a wasted concept presented poorly and defended rudely.

Regards,
Alan

typer_801

Thanks Alan!

And DB1-R81 -, When asking questions to elicit "opinions" please don't flame those people who respond, especially you really don't have any experience or knowledge on the subject other than some second hand information which you you really can't validate anyway. After all this was someone else's tip which you had no idea if it really worked or not.

Going further, if you would listen (or read in this case) instead of flaming, knowing it all, whatever you want to call it, you might actually learn something from other people's responses.