Currently I am running 2-v heads on a 351 cleveland. How much of a diff. would it make if I changed the 2-v heads for 4-v , also which 4-v heads do I need? What is the diff. between closed and open chamber heads
The 2-v heads are great for the street. The big port, big valve, closed chamber 4-v heads are better suited for racing. Closed chamber simply means the combustion chamber in the head is smaller resulting in a higher compression ratio. How will the car be used? That will help you decide the type of head you need.