im not sure if this works in the professional races, but for any A, B, or IB race, use n2 tires; it makes your grip equal to the AI which causes some fantastic competition. it can be frustrating making your way through the pack to win it on the last lap, but it is a blast. youll have to tweak your car to win some races (the SL cup i had to buy an SL65 and do all tuning except power to barely win) and the Aspec points vary, the SL cup was at most about 12 points, but i have gotten as high as 177 points at different races. also in using the tires, you cant outbrake or outcorner the AI, so it makes it a lot more realistic.