First yes I have searched and because question has multiple levels to it, I need some help.

I am getting some Ruff 278 18/9.5/+20 rims rear and 18/8.5/+20. I am now looking for tires. I was thinking that 275/40/18 rear and 245/40/18 should work without rubbing.

Issues I am trying to avoid

a. Speedometer reading off.
b. TCS being affected
c. rubbing

a. What does the speed sensor read. I am ignorant of this. If it reads wheel speed, which wheel as I would like to be as close as possible.

b. Don't think this will be a problem as I am below the 3% threshold every writes about.

c. Don't think this should be a problem ither as I have seen a lot more aggressive setups that owners say don't rub. My car is not lowered either but do plan to do so before summer '08.

Any ideas or advice I would appreciate greatly and if I have missed something in the search that will answer my questions point me in the direction please, but I would like some persoonal thoughts on those that have experience with this.

TIA

 

A tire calculator is your friend. Match the OEM tire height, and the speedometer will be fine.

TCS is less susceptible to problems the VDC, still, I recommend that the rear tires be 10mm taller than the front.

 

I did the tire calculators already how I got the tire specs I have there. Why does rear need to be 10 mm taller?

 

bump

 

TCS can cope with just about every tire set-up. Here the rear tires are 24 mm taller than the front. I see no problem.