It all depends on the how much your willing to spend and what size rims you use. Also another factor to concider is what you will be racing, a great Road Racing tire is just a good Autocross tire due to the different temp ranges the tires work properly. Hooisers A6 is a great auto cross tire works at the 140-160 degree F range and a R6 is a great road race tire working in the 160-180 range. Toyo Ra-1 are decent in the dry and wet, shaved ra-1's are are sticker but are not as good in the wet. Your other option is to contact a SCCA World Challange ST team and see if they have take off tires (Pirrelli). Also a Contenental tire series team in the ST class would have take offs you might be able to pick-up. Race teams have piles of take off tires and this is the time to pick them up for cheap. Falkens are good also btw.