Originally Posted by BGTV8

I run 275/35R18 on 9.5" Enkei for wets and 27/65R18 Michelin Slicks (actually Porsche Cup fronts) on 10" Braid Forged. Alternative slick is Pirelli 285/655R18.

Square all round makes for better balance - Unless you are boosted and running mega torque, I'm not sure that anything bigger than 275/285 provides a benefit