1966 1967 1968 1969 1970 1971 1972 1973 1974 ALL CYLINDER HEAD ASSEMBLY

Part Number: 12464298

ALL  CYLINDER HEAD ASSEMBLY - Part Number 12464298
Cylinder Head Assembly Aluminum fast burn. Fast burn cylinder head combines new technologies with the best of GM Motorsports and the production cylinder head programs to create the highest performance potential of any 23-degree small-block GM cylinder head. Fast burn technology maximizes combustion of the air/fuel mixture, resulting in higher cylinder pressures and more power production. The combustion chamber (62cc) is designed for flat top pistons, and the head requires no additional porting for optimum performance, so it provides maximum "out-of-the-box" performance. Rocker cover rails are taller than normal and CNC-machined for exceptional rocker arm clearance and rocker cover gasket sealing. Early-style perimeter-style and center-bolt valve covers will bolt on. Intake manifold mating surfaces are drilled and tapped for ether Vortec-style (recommended) or raised-port-style manifolds. D-shaped 78-cc exhaust ports and runners provide adequate flow for 500+ horsepower applications. The head assembly includes 2.00-inch hollow stem lightweight intake valves, 1.55-inch sodium filled lightweight exhaust valves, high-performance valve springs, lightweight valve spring retainers, screw-in 3/8 inch rocker studs, and all necessary valve springs caps, shims and seals. These head assemblies can be used on any 1955-2000 283-400 small-block with conventional water flow design. Heads provide a 25-horsepower increase when used on the ZZ4 crate engine. Note: Exhaust headers with LT1/LT4 style flanges are required. Heads cannot be used on LT1, LT4 or Gen III/Gen IV engines. GM Performance Parts cylinder heads are created with GM premium-engineering, then cast and machined to our exacting manufacturing standards. GMPP cylinder heads are available as bare castings or complete cylinder head from service replacement castings to all-out competition applications.
Aluminum Fast Burn 1966 1967 1968 1969 1970 1971 1972 1973 1974

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