O.K I want to go 8" front and 9" rear..wheels chosen.

I had thought I'd done tire calc correct with 1.4% rolling diameter diff from stock eg. 225/45 18X8" front and 265/40 18X9" rear.


However,now apparently I have a problem with circumference differential between f and r. Stock 18's have 50 odd mm diff and my arrangement has 30mm odd.
help please.......sorry to be a pain

Steve

 

you need 245/40-18 front and 274/40-18 rear....

 

on the 8 & 9" 245-40 & 275-40 is obviously ideal. Stock was certainly not a 50 offset. Stock is +30 f +33 rear.