Big Block Power Combo - Real Fine 509, Part 2 Photo Gallery
The fast burn-style combustion chamber design of the Pro1 heads promotes quicker, more complete combustion. The chamber volume is a relatively larger 121cc. Both the intake and exhaust valves are rolled 2 degrees from stock: 24 degrees vs. the stock 26 degrees on the intake side and 15 degrees vs. 17 degrees on exhaust side. The intake valves measure 2.250 inches in diameter, while the exhausts are 1.880 inches.