Stock LCR alloy tyre fitment is 225/40/R18. Why would you want to run a wider tyre than the wheel is designed for? Aside from any (possible) safety implications you're creating more rolling drag, thus reducing performance. You may also find your insurance is void as a lot of insurers will refuse to cover you if you're running tyres of a different fitment than the wheels are designed for.
+1 on the Vredestein Ultrac Sessants though, I'm on my second set and they're fantastic. They come in standard LCR fitment though, Camskill have them.