How wide of a tire can I get away with without rubbing...

 

Best guess, according to the plethora of information you posted, Stock width.

 

https://www.rx7club.com/suspension-wheels-tires-brakes-20/official-fc-wheel-fitment-thread-257700/

 

He doesn't need wheels, he needs tires.

read, it's only ONE line of text.

 

lol FAIL

 

It has what TIRES will fit on all sizes of wheels for the FC in there too...

 

let's see how this pans out.

 

right now I have on 215/40/R17 and have excessive outer edge tire wear on the front right. Had the front end checked out by a shop and everything is tight.

 

I was running 225/50/17. No rubbing at all. This was on my 88 gxl.

 

Does 50's cover the wheel well gap, car's not lowered and I don't plan on doing it, thinking about 45's or 50's

 

What width you can run is entirely a function of what wheels you have. If you have crazy negative offset wheels then they'll be sticking out past the fenders and no matter what tires you run they'll always be rubbing. If you've got too high an offset they'll hit the suspension and you won't be able to run any tire without rubbing.

Assuming you've got acceptable offsets and widths, about as wide as you can go with some work (ie rolling fenders) is 245 in front and 275 in the back. A safer bet is 225 and 255 if you're not willing to work at making it fit.

Both those tire sizes aren't what you should be running. 215/40/17 is too short, you should have a 45 series sidewall to match the stock diameter, the 225/50/17 is too tall, you should also have a 45 series sidewall to better match the stock diameter.

 

awsome info thanks Black91n/a
I think i'm gonna go with 225/45/R17

 

50's cover the gap just right! It tech is bigger than what stock should be (45's) But I had no problem with rubbing at all. Also my car has the stock suspension. So if you want to fill the gap then go 50.

At first I ran 45's and my custom wheels(17's) were within spec. I found a used set of 225/50's and tried them out. Worked great and bought another set of 50's the next go round.

 

right now i'm running 255/40/17 all corners.had to roll the front fenders for it not to rub w/ coilovers.

 

What is your wheel's offset?

And are you sure it's not camber wear? you may need to get that adjusted.

 

If the tires are larger than stock then you'll be hurting your gearing, making the car slower.

 

17x7

as stated above I had a diagnosic of the front end done and everything checked out good

 

That is not your offset. And all you said was everything was tight, nothing about you getting your alignment checked out.

 

225/55/15, 225/50/16 and 225/45/17 are all about the same size, height-wise.

"but the profile is bigger!" You say.

This is why people need to be educated on exactly what these numbers mean.

 

An alignment that's "in spec" can still lead to that wear. If you're driving hard you'll need more camber or else outside wear can be the concequence.

 

tires
http://fc3spro.com/TECH/MODS/RT/tires.htm

rims/offsets w/ tires
http://fc3spro.com/TECH/MODS/RT/rims.htm