planning to get some slick for the track but not sure what size to get. i am leaning towards a set of kumho Ecsta V710.
my current rim size are 18x9 in the front and 18x12 in the rear so the question is if i can use the same size tires as my street tires without rubbing or do i have to move one size down for the rears?

 

I have a set of near new OZ Ultraleggera 19" x 8.5, 12 wheels with Hoosier slicks FS. PM me if interested.

 

You have two choices with the Kumho 710:

for near-stock wheels:

245/35R18 8-9.5" NA 24.8"
285/30R18 9.5-10.5" 11.4" 24.8"

or for your larger wheels:

245/40R18 8-9.5" 9.1" 25.7"
305/30R18 10.5-11.5" 12.3" 25.5"

I know the smaller tires won't rub. I don't know about the
larger ones, but when I wear out my smallers, I will be
trying those larger ones next.

HTH,
Joe

 

OT - Melsta, high res of your avatar??? Looks VERY nice!

 

have you tried the HoosierA6 and R6? any rubbing with the 245's up front? so i should stay away from the 315's for the rear? Thanks

 

i think its in my old computer i'll try to look for it

 

For Hoosier, for stock wheels:

P255/35ZR18 10.3" 24.8"
P285/30ZR18 10.9" 24.9"

for your larger wheels,

P245/40ZR-18 M 9.3" 25.3"
P315/30ZR-18 M 11.4" 25.6"

I can't be sure about rubbing with any big tires.

 

Joe, why choose a narrower rear wheel setup for track on stock rims. Wouldn't the logical Hoosier track set up be

R6 245/40/18 8-9.5" rim 25.7" diameter
R6 315/30/18 11-12" rim 25.6" diameter

 

For straightline performance the narrower width will have greater forward directional traction. For road course, the one's you have listed will be better.

 

I suspect that the larger ones may rub, but if they don't, that would be the way to go.

 

I have 315/30 rears and they don't rub with stock rims. I just added 15 mm spacers and no rubbing on the outside either.

 

And how about the fronts? No rubbing at large steering angles? (I'd tolerate that).
Is your car lowered at all?