Our buddy Rick Riccardi at Downs Ford Motorsport dropped us an email about a new product the company is offering. They teamed up with renowed cylinder head porter, Dave Jack Cylinder Heads, to produce a specially ported P.I. Two-Valve cylinder head. It has been dubbed the Dave Jack Signature Series. Plans for other cylinder head CNC-ported options are in the works.
Dave Jack starts with new Ford Racing castings and he designed special ports for forced induction and naturally aspirated combinations. The intake port volume measures 180cc and flows 221 cfm at .500-inch lift. Moving to the exhaust, the hole is 80cc and moves 198cfm at .500-inch lift. The valves are from Ferrara and check in at 1.78-inches on the intake side and the exhaust valves are 1.45-inches. The combustion chamber is listed as 50cc. Downs equips the heads with Manley Nextek valve springs.
Rick didn't tell us about any comparisons to stock but we know Dave Jack. He is one of the premier head porters, so you know these heads will help your modular engine produce big power.