My first choice is the BFGoodrich g-force T/A KDW's, because thats what I have & I love them!!! My next suggestion is Pirelli, although not the best looking or longest lasting tire, they stick like crazy. When I had them on my 18" Saleen rims I tried & tried to get them to squeal on corners & it was very difficult. They hold on corners very well. I have been told that the Michelin pilot sport is very grippy, but I dont know for sure. I have a pair of 285/35's sitting in my garage that I bought for a rainy day. I just havent put them on. You wanna buy those!?
I know some people will suggest Nittos, & other rice tires, but I dont recommend them. Rice tires are for rice cars, small & powerless, IMO. Go to tirerack.com They have good reviews & ratings, they should be a big help in your decision.
Best gripping tire that will fit 18'' rims? 
