the rear you will prob have trouble with the fuel tank plastic cover, especially if ur running camber at around 3-4 deg. and yeah 225 on the rear will suffice.. i have 215 on my 17x9 rears atm its fine
Na man ! It's fine! When I had -8 it completely burnt through the plastic. But I was on LMs at the time and my car was on springs. It's just all trial and error as it is different for everyone (dependent largely on height, wheels and tyre stretch.