Well I read what I posted and realized it was 7500 rpm, my bad should have looked at it better. Stock X heads no porting other than a 3 angle valve job, stock size valves. Only allowed factory spec pistons with 5/64 ring pack, stock rods, stock stroke crank (318). Intakes is the factory cast iron for a Thermo quad, nothing changed on it either has to have the choke. Cam is any duration with stock lift for the 340 (.450 I think) can be solid lifters now. Stock style springs and stock retainers, 273 adjustable rockers. Any header. Watch one of these cars in action (standing on the back bumper) and you’ll be blown away. The 318 cars from 78-85 can use the same pieces but smaller cam and they’re down 5-6 classes running mid 12s. They can’t compete with the 340 but still run on their index. Biggest tire allowed is 9” wide. If the 318 could do what is being said it would be out there