88gxl

I have a set of 18x7.5 inch wheels sitting around and wanted to know the widest tires i can fit on them for the rear of my t2. i have 225/40s on them know, but i need 2 new tires. Would 235 or even better 245 fit?

Samps

Depends on the offset, but I think people have gotten 255s out back.

88gxl

But what is the widest i can go on my wheels. They are only 7.5in wide. I don't want the tires to look too wide for the wheels.

T2 Tsunami

iTrader: (3)

I have 17 inch rims, 7.5 wide. My tires are 235/45/17..and that"s all around, I have no problems with scraping, not even on hard turns...just have to check the off set on your rims.

V8RX7com

I’ve done a lot of research lately on tire sizes because I want to reduce my gearing with a taller tire in the rear with my V8 powered RX-7 convertible. Reducing the gearing in my car is a good thing because I have too much torque with the V8 and not enough top end speed, but the opposite it true with the rotary powered RX-7, because with the rotary, you have plenty on top end but not much low end torque.

On a 7.5 rim with a 40 series tire a 245/40/18 is the widest that will fit comfortably on the rim but keep in mind a 245 is going to be about a half inch taller then a 225 and will change your gearing slightly.

If you had a wider rim on the rear, a 265/35/18 would be a good choice because it would be about the same height of the 225/40/18

Some things to think about:


Going from a stock RX-7 205/60/15 to a 225/40/18 (with a 5spd tranny) you have reduced the rear gearing from a 4.10 to a 4.06 ….. Most likely not enough to notice.

But going from a stock 205/60/15 to a 245/40/18 you have reduced the rear gearing from a 4.10 to a 3.95 and this is enough where you will most likely will notice a reduction in torque.

My point:

I see a lot of people wanting to go with the widest tire possible thinking it will give them better performance, but that is not always the case because sometimes people forget about how different sizes effects gearing