Guys....I will need some new tires soon. I was thinking about jumping up to 255's...keeping my stock wheels. Will I have an issue with rubbing? Also, I guess I would have to get 255-40-18's? thanks

 

stock wheels are only 7.5 inches wide. They won't fit a 255 wide tire. Not safely at least.

 

255 ares more of a sidewall size??? I have them safely for 2+ years!!!
http://www.miata.net/garage/tirecalc.html

 

I don't think that calculator takes into consideration the rim width.

 

I thought your OZ rims were 8 inches wide. no?

 

I believe stock rims only allow up to 245 widths. My 9" wide rims have 255 and I have had 265 widths on them and I have heard of 275 widths. But this is for wider rims.

 

http://www.1010tires.com/tiresizecalculator.asp

This takes into consideration the rim width.
The most you could do is actually a 225 on a 7.5 wide rim (225-40-18)
235with a higher series tire but it would throw off your speedo quiet a bit


On my 17x9s I had I could fit 275s on there if i wanted to

 

well the stock 6th gen wheels on the SE are 18x7.5 and they come from the factory with 24/45/18 tires. The sidewall sits flush, no stretching or bulging.

 

Opps Sorry the thing didn't reset correctly when I was checking sizes early. My bad.

but 255s would still require an 8" wide tire

 

I had 255-50-16 tires on my 1994 Firebird Formula, and that was a 8.0 inch wide wheel. 255 is the widest you can go on an 8.0 inch wheel safely, so 7.5 wide wheel wouldn't be safe.

 

A tire shop shouldn't mount it...for liability purposes....I say shouldn't because i've seen some shops do some stupid things.

 

Some shops will mount it, but they'll do it at YOUR own risk... it's like tinting front windows or windshield... you take the blame, but I personally wouldn't do it.