Hi people, I am very new to the RX7 world.
Bought a 1999 RX7 that was originally an AT that was converted to manual.
It currently has 18 inch wheel with 240/45 tires that is rubbing and you can tell that speedometer was reading lower than the actual speed of the car
what is the stock size wheel and tire aspect ratio combo in terms of overall height that will give me an accurate speed reading without rubbing?
esp looking at 17 inch wheel

Thank you guys

 

FDs that came on 17s rode on 255/40/17 that have a diameter of 25in.

An 18" wheel with 240/45/18s is 26.5in in diameter, so a fair bit larger. You'd be off 4 or 5mph at highway speeds. It might cause big rubbing problems, but I suspect the rubbing is more a problem of possibly being lowered or a poor-fitting wheel offset. Someone putting that large a tire on likely did not do due diligence on a correct offset