So I always assumed my 351c had 4v heads on it but after some research I looked and there is a 2 stamped above the drivers front and passenger rear exhaust port. It has hooker super comp headers which are for 4v heads I believe. The intake is a cast iron Ford 4v intake with a demon 750 DP. I guess I should swap to an aftermarket intake for the 2v heads but wanted to hear different opinions. What about the headers? Carb size? Note: I run a T5 with 3:50 gears car has a healthy cam mallory dist and a msd box and runs decent. Definately needs a little tuning but I think the intake and carb issue could be part of tuning issues.