Ok, now I know that there is a Sticky thread about this, but I couldn't find what I'm looking for...

The stock tires on a '91 rx-7 are 205mm/7in in width... how big can I go without spacers needed? Can I go 8"?

 

you can go as wide as you want...with enough money. but anyways ive read that you can go as wide as 275 safely. dunno if that is with a spacer or not. sorry if not too much help.
-t

 

well... lets put it this way.. how big of tires can I fit on a 7in rim? -- again, not needing spacers?

I did this mm to inches conversion thing online and it said that 205mm converted to 8.1 inches???

 

Are those 16's or 15's. I put 225s on my 2nd gen 15's.

 

15s... but it shouldn't matter should it? I'm looking to get some 17" by 7" rims, so as long as they are both 7", I guess I could fit 225s on there too... and that'd be enough! Any problems fitting them?

 

I had no problems fitting or rubbing with 225's on my 15's. True I do have coilovers but the tires were installed prior to the coilovers. I think 225's on the 15's are just about as large as you can go, I could be wrong though. If you are upgrading to 17's or just different rims, the rear will fit like a 285 or something and the front will only fit like a 255 or so. Don't quote me on those numbers though.

 

oh, just noticed you only what a rim 7 inches wide. You may only be able to get 245s on that, not sure.