2008 GT. What is the largest diameter and widest stance of rubber I can put on these rims?

 

The max width of tire fitment, depends on the width of the wheel in question.... what is it?

Why are you looking to go larger diameter, as this creates a few issues that are not always good.

Jazzer

 

Don't know the width. They are OEM 17" wheels. Want to go larger because in all honesty the 235/55 17's look too small for the wheel opening

 

They are either 8" or 8.5", depending on some options. If they are 8.5"s, you can run up to a 255, but that is it. I recommend you look to pick up some aftermarket wheels and can go up to 9"s & 10"s easily.

Jazzer

 

Running 20's right now. Actually, you freaked when I told you the size of the rubber I'm running. Just want to get back to the stock look. And 255x??17

 

OK.... I just searched and found What profile for 20's? thread

Your OEM tire diameter is a smidge over 27" diameter and was a 235/55/17". If you're looking for new tires on your OEM 17" wheels, you are relegated to what I mentioned in my post #4 above.

Curious as to why you want to go back to your original wheels?

Jazzer

 

OK so 255/55 17. I'm putting lowering springs 1.2" all around, and I'm sure the 20's will rub. Also, my braking does not SEEM as confident as when I had the 17's on. I even went with EBC rotors and Red Stuff pads.

 

If your tires are larger diameter than the OEM ones, then your brakes will be effected, to some degree. This depends on other factors as well, so might just "seem" like it, as you mentioned.

I have a write-up on brakes in my sig and may be of some help.

Jazzer