Speedmaster PCE281.2169 Pontiac 400 455 230cc 69cc Ram Air IV CNC Hydraulic Roller Assembled Cylinder Heads

Speedmaster Pontiac heads include valve sizes at 2.11" Intake, and 1.66" While the 2.11" valves are standard issue, the valve seat can be machined to accept a larger valve with minimal work. CNC Ported heads in this application will soon be available.Speedmaster CNC ported cylinder heads are machined on dedicated 4-axis and 5-axis CNC machining centers to ensure accuracy and cost effectiveness.On the CNC ported versions, combustion chamber, Exhaust and Intake Ports all fully CNC machined for better flow. CNC combustion chambers offer superior control over flame travel and quench area. CNC Ported heads eliminate human error and variation from port to port. Unsurpassed repeatability from one cylinder head to another that is commonly found in "Hand porting & Polishing"Combustion chambers are exact in volume - so every cylinder has the same compression ratio. Each port is the same cross section - so every cylinder can reach higher true RPM potential.

• Assembled with the finest premium components to provide your engine with optimal airflow for maximum engine performance
• Improved power throughout the rpm range for greater throttle response and top-end horsepower