Upgrade size on 08 MS3 with Mazdaspeed forged rims

[LovinMyMS3]

Hello I was wondering if somebody could answer a question for me or point me in the right direction. I'm trying to find out what the biggest tire I could fit on the Mazdaspeed forged rim with stock suspension. Thanks for any help.

 

[CnoTataymo]

Since they're 18x7.5, people usually run....

215/45's, 225/45's, 225/40's or 235/40's.

 

[LovinMyMS3]

Thank you.