Can you change the tire profile(aspect ratio), from the stock 60 to maybe a number like 50, and have it still ok if the tire has the right width and diameter?
BTW I have a 91' n/a. Thanks

 

yes, look it up

 

Depends on whether or not you want to maintain the OEM overall tire size and odometer/speedometer accuracy. If you drop the aspect ratio from 60% to 50% and don't increase the rim diameter, your odo/speedo will be inaccurate. But if you go for a 1" larger diameter rim and drop the aspect ratio as stated, you will have about the same overall wheel diameter/circumference as the OEM wheels.

 

I had Kuhmo 711's in size 225/50-15 on my previous NA.
They were a bit wider than the chart, but they gave excellent grip with about 1" of tread shift entering a corner and no speedometer error.
There is one on ramp I could take at 100 in that car that I can ounly take at 95 in the turbo.

And - they are not expensive.

 

There is a link for a Tire Size calculator found in the FAQ for FC sticky thread as well as in the Wheels/tires section of this board.

It will allow you to put in what size tire you have and then what size will give you the nearest to that size in a different profile.

Please read the FAQ for FC sticky thread, found at the top of the 2nd gen RX-7 technical section before posting!

 

You can also find actual tire dimensions (treadwidth/circumference/height) on the TireRack website. All the tire size calculators in the world won't give you what you want if the actual tires vary (which they do).