RX-Ben

For running a square 275 setup - is there any reason (performance-wise) why I would want to use 17x9.5 wheels all around instead of the 18x10.5?
18s are a little heavier, but will give a wider contact patch (~.5").

Thanks.

sperkins

The 17" wheel does not support the sidewall as well as the 18".
That being said, I've been wanting to try 18's on the front and 17's on the rear for some of the tracks we run. That extra sidewall may actually help on corner exit.

drivinhard

the 9.5" are lighter and you have more sidewall, the 10.5" seem to make the car a bit more stable and turn in is better.

it really could be track dependent. (and tire specific, all 275's do not measure the same)

travisnd

I had some 275/40/17s left over from another race car so when I first setup my car I did it on 17x9.5s all around. The car felt ok, but on the advice of the two bozos above I tried the 18" setup.

Car was 100% better on the 18s. I'm currently running a 255/35/18 on 4 rear Z06 wheels.

RX-Ben

Thanks for the info.

Allthrottleandsomebottle

FWIW,
I ran these on my 97' square at VIR full track and they did very good:
OEM MAG 18 x 9.5 w/ new Hoosier R3S05 275/35/18 road race radial 4.532nds tread with std valve stems 42lbs ea.
Danny Popp thought they stuck pretty good..........

travisnd

Sweet... I don't think I've ever seen anyone take pics from the inside of Oak Tree!

Kubs

Cool picture!

This year I am going to try 275s on 18x9.5 wheels as well (C6 Z Fronts). Everyone seems to put the 275s on the 18x10.5 wheel so it nice to get some feedback on other options.