[vtirocz]

I'm considering to put SS 1LE tires (Goodyear Eagle SuperCar 3) tires on my SS wheels after the stock runflats wear out, however they are not available in the exact OEM SS non-1LE sizes (but very close!). I'm interested in thoughts on going with the following setup:

Front:
Stock SS wheels with Goodyear Eagle SuperCar 3 tires
255/40/20 (instead of original size of 245/40/20)

Rear:
Stock SS wheels with Goodyear Eagle SuperCar 3 tires
285/35/20 (instead of original size of 275/35/20)

The only problem I see is the slight difference in tire diameter with this change.

Here's some calculations below.

What's everyone's thoughts on this setup for a more aggressive street / autocross / track setup? The goal is to get closer to an SS 1LE in performance. I eventually plan to add the GM lowering/handling kit as a "budget 1LE" setup. Thanks in advance for feedback.

[samr350]

You'll be fine, overall diameter change doesn't matter, you just want to stay within 2% front to rear and you'll only be at 0.6% with this setup. This will be a great improvement as far as handling goes too. Also use the USAA discount if you can and this will be pretty cheap too. I'd also suggest a performance oriented alignment as well which will make it drive better and wear better on the track and at autocross.

[vtirocz]

Thanks for that feedback! Has anyone run that tire size of 255/40/20 front and 285/35/20 rear with the GM lowering kit (or similar) AND track alignment specified in the performance supplement manual. If so, any rubbing issues?

The diameter change is so tiny that I can't imagine there would be, but I'm interested to hear from anyone with firsthand experience on that setup.