Dude if your car has a bit better springs than stock you would do just fine! Last time I went the competition was as follows:
2001 Porche Boxter
1994 Rx7 TT
1985 Toyota MR2
1995 Eclipse RS
2001 Honda Accord (bone stock with about 1500 miles on it)
BMW M5 (fastest on the track, set up for full race, car was in the strictest sense "street leagle")
So if your worried your car won't perform, dont! It is all about fun, and there are pleanty of places to pass on so if you are a bit slower it isn't a problem. We don't race like the Australian Touring cars, no bump to pass shit here.