Quick view Edelbrock RPM CNC Cylinder Heads 72cc Round Port These Edelbrock #61515 Performer RPM CNC Cylinder Heads for 1962-79 389-455 c.i.d. Pontiac engines feature 2.11 intake valves and 1.60 exhaust valves. They are set up for use with a hydraulic roller cam and have the new 72cc CNC machined combustion... $3,000.00 Compare