Tires size for AutoXing

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BLAAK
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Tires size for AutoXing

Post by BLAAK »

How's running 225 up front on stock rims feel compare to putting on 205?

Next year, I will be competing with my ITR and would most likely run on 205 but I hear that some of you guys run 225. I just want to know what's your experience. Has anybody tried 215 on all four corners?

Blaak
bbqman
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Re: Tires size for AutoXing

Post by bbqman »

More grip in the front with the 225's, a must for the compitition at National level. Keep the 205's in the rear for rotation on sticky surfaces but you can go with 225's on slippery surfaces.
think you need a spacer for the rear though, check for stock class eligibility.
See ya this weeekend.
TypeR 801
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Re: Tires size for AutoXing

Post by TypeR 801 »

Night and Day difference. The car finally does what you want it to (in stock form) with the 225/205 staggered combo. It's the *only* way to be competitive in a stock class R.
BLAAK wrote:How's running 225 up front on stock rims feel compare to putting on 205?
Jeff Brown
98 ITR #801
VtecWhore
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Post by VtecWhore »

well what i was told but not sure its true but for auto x i heard a low profile tire is better. so on stock itr wheels like a 195/45r15(slicks) would be good. 45 has less roll. and the 195 is a less wider tire so theres more pressure per square inch than compared to a 225. i would guess a 205 might be okay too. i ran yoko advan 205/55r15 and it was really nice. just my 2 pennies.
nw98typer
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Post by nw98typer »

Your right about the lower profile, since in general it can improve the vehicles gearing. However, for autocross, you really want the width for the ultimate grip.

With a 195 or 205, I think the car would tend to push more for a given amount of power. Because of that, you wouldn't be able to roll onto the gas as soon.

I don't think that higher pressure is a good thing, either. You're goal is to run the tire as soft as you can (max contact patch), without having it roll over onto the sidewall where there's no tread.

HOWEVER: When it rains as much as it did at Nationals and all the R's are running dirt stockers, all this goes out the window and the biggest oar wins.
bbqman
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Post by bbqman »

VtecWhore wrote:well what i was told but not sure its true but for auto x i heard a low profile tire is better. so on stock itr wheels like a 195/45r15(slicks) would be good. 45 has less roll. and the 195 is a less wider tire so theres more pressure per square inch than compared to a 225. i would guess a 205 might be okay too. i ran yoko advan 205/55r15 and it was really nice. just my 2 pennies.
while the arguement about low profile holds somewhat true, when purchasing r-compounds for autocross you must chose sizes among what exists. As far as I know 195/45r15 never existed in any performance offering and 205/55r15 same story and for sure not in Advan.

So ....as not to confuse anyone who is planning to buy R compounds for autocross use.......the setup regarded as THE way is minimum 205's all around, but best case would be 225's up front.
Until offerings change size wise, this is the fast ticket.
Who knows, Hoosiers new offering may shuffle the cards again.
TypeR 801
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Post by TypeR 801 »

The Hoosier 225's are labeled as 45 series but are more like 40 series given they're diameter. They're still the hottest tires for an R and will be even better in 04 with the new design.
Jeff Brown
98 ITR #801
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