doesnt sound right to me
Hi all, I have changed wheel and tyre sizes on so many cars I have lost count Biggest admittedly is 18" from 15" but I have never noticed more than a minute difference in fuel consumption but usually for the better, so I suspect you have another problem with this car that is causing this extra consumption, to use so much more fuel the OD would need to be smaller by quite a margin.
I dont believe that this is the case.
Ps. There used to be a website that had all the tyre size info on it Try google! (I just found it 6.17 % is the OD increase)
so you should get better MPG as that would reduce rpm speedo will be slighly out too and Milometer.
Last edited by Alfa male 1; 18-10-11 at 13:12.