the piston discussion that HakenTT started. The thread is locked. The Honda S2000 and the < 99 viper engine have forged pistons. Not only for pro stock but on street cars as well . Hakentt has claimed forged pistons are only for Pro stock. I was right Honda and Viper have forged pistons on some of their cars, not all. The '99 and above Vipers switch to cast pistons.