What size semi slick on a 15x8" +36 6uL wheel on an em1?

[fatboyz39]

thing is i'm already running 205's all round. I want to get 225's at the front to attempt to get a little more grip in the tight turns (cows titts at winton) and also on corner exit.

Run the 205's on the 15x8 first to see how it feels.