Tire height afects on gear ratio?

[mikemcvaney]

Switched to 275 sixtys does anyone know the formula for tire height and gear ratio affects? Mike

 

[charlief1]

WebCars! Tire/Wheel Compensation Calculator

 

[bison]

Using side wall numbers doesn't usually work out. The best thing is to measure the actual height on the car. Whatever % difference in height you go up or down is the effect. There is some growth to be considered at high speeds also.

 

[mikemcvaney]

thankyou gentlrman. Mike