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Discussion Starter #1
:confused: Before I take the plunge and order this size, does anyone think that I would be better off with the stock 245/45? Before I can afford an extra dedicated autox wheel/tire setup, this will be my street, open track, and autox tire. I would like to take advantage of the extra width(about .4-.5) and the lower OD(about .7), but the book lists the minimum width as 8.5". Will the tire be "pulled in" too much and compromise the contact patch and tire performance? Or am I just splitting hairs? :idunno:

Thanx,
 

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i have that exact tire on my 04, stock 17x8 rims.

DO IT... i absolutely LOVE these tires and they look awesome of the 8" rim. Fill it out very nice with no huge bulge, looks right at home
you wont be disappointed
 

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this will be my street, open track, and autox tire.
Of the three uses, auto-X is probably the most tolerant due to the very short driving durations and near-empty load conditions involved.

Mostly, this is a heat generation issue, and where in the sidewalls the heat tends to concentrate. As wheel width varies, the flex point moves up/down the sidewall slightly.

I'm more wary concerning your other two uses, where even though the intense use isn't quite as continuous - the fact that they're more sustained activities more than makes up.

Half an inch is only marginally "out of spec", so it's not like you're way off on the wrong side of "pass/guaranteed fail". But I would avoid doing things like loading the car up to the gills and then driving it several hundred miles on a hot summer day.

A 255/40-17 is one load index smaller than 245/45, or about 45 lbs. Load capacity-wise and heat-wise, the advice would be to air them up about 2 psi over the sticker inflation numbers given for the 245/45's. That might cause the tread centers to wear a little faster, though.


Norm
 

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Discussion Starter #6
i have that exact tire on my 04, stock 17x8 rims.
Thank you. This is what I needed to hear. Have many miles do you have on them and any adverse wear?
 

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Discussion Starter #7
Of the three uses, auto-X is probably the most tolerant due to the very short driving durations and near-empty load conditions involved.

I'm more wary concerning your other two uses, where even though the intense use isn't quite as continuous - the fact that they're more sustained activities more than makes up.

But I would avoid doing things like loading the car up to the gills and then driving it several hundred miles on a hot summer day.

A 255/40-17 is one load index smaller than 245/45, or about 45 lbs. Load capacity-wise and heat-wise, the advice would be to air them up
Norm, you're really throwing a wrench in my works. :curses:

I was more concerned with the rim width affecting the tire in a performance driving mode than street driving. Didn't think about that load range aspect.
And I am planning to drive out to SAAC 34, at Beaver Run, a good 350 miles, in August, run 3 days open track, yada, yada, yada. Maybe I should plan to have that extra wheel/tire set by then.....and put 'em in my friends trailer. Thanks for the input. :salute:
 

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Discussion Starter #9
Long, long ago in a galaxy far, far away, I ran 255/40 Comp T/A R1s on 17x8s. The worked great, no issues at all.
Hmm....Sounds like an era I remember well. maybe even a few trisecs before that. At that time I was moving from 225/60/14 A008R Yok's to a 225/50/15 BFG R1 or a Hoosier Autocrosser(bias ply) for my '66. Thanks for the reply, I'm going with the 255's. Now I just have to decide if I want to shave 'em. :idunno:
 
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