Originally Posted by maxcichon
It looks as if the sidewall is under alot of stress with 8.5" rims!
I thought about that but the stock 7.5" rim doesn't stretch the fronts at all. An extra inch should wrap the front like the rears are stock. And I've seen 8" wide wheels support 225s without stretching them at all.
Guess it depends on the tire manufacturer.
Originally Posted by blackoutken
would 255/35/20 rear be far off
3.8% off. Too far. Try a little thinner on the rear. 235/35R20
And to address Max's concerns, make the front a little wider too... 235/30R20
Check the availability on those.