275's will fit. I ran 245's on a 7.5" rim forever, and we have 9" in the back stock. Fronts are 8" and will support a 245.
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'10 PW 370Z 7AT - wife's car - Project Raspberry Cheesecake
'08 Evo X - built motor+trans | BB-X @ 32 psi | CH3OH | self-built+tuned - ??? WHP
'01 Galant V6 - built motor | GT35R | self-built+tuned - 550+ WHP (retired) |