Yup
F R Dia. Diff
OEM Rays - 225/45/18 245/45/18 2.73%
My Rotas - 245/35/18 265/35/18 2.23%
20s - 245/35/20 275/30/20 -0.88
Now my Rotas arent the OEM spec rolling radius, but they keep the front to back stagger. Thats where yours goes wrong I think. As Andy says, you need 30 profile on the front. That puts it back at 2.75% stagger which would be fine.
Sure Phil/Kev/Adam will correct this if I'm wrong!