bart speaks the truth
i use 18x10 and 18x11.5 simmons , and in australia a set of tyres to outfit those wheels will cost around $3000
i went with pirelli corsa's
if you want to go fast at the track you need to rubber up :nods:
grip is one thing, but the biggest reason I was running 18x10s and 11s was for heat disipation. in the summer, my 265f / 295r r compounds were not enough for going fast. They couldn't simply shed the heat they build up and they would get super greasy and sometimes chunk.
Terry's setup will take some work to get them to fit. but 10s and 11s will bolt right on with a little rear fender rolling.
One day at the track I corded my drivers front tire and didn't have a replacement . so I put on one of my 305 rear tires it was tight but the grip was unbelievable on that side,gained more than 5mph in turns 2,8 and 9 at WSIR but did have some rubbing issues, only ran it that one day.