My 225s are 20x8.5 fronts with 255-40/20 toyo proxes STII tires and 20x10 with 295-40/20 toyo proxes STII rears. 4.5" backspace front and 5.5" backspace in the rear.
I need to roll the lip on my fronts, since they rub a bit when going over a bumpy turn. In my opinion, the backspacing is right on, unless you're going for hellaflush.
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