Chevy SBC Assembled Aluminum Camel Double Hump 461 Cylinder Head

• Features 180cc intake runner, 62cc exhaust runner, 2.02" intake/1.60" exhaust valves, 1.560" max spring pocket diameter.
• Cast from premium quality aluminum that shaves 40 lbs. off the nose of your car vs. heavy iron heads.
• Comes completely assembled with no accessory bolt holes, just like the original heads.
• Improved port/chamber shape for better performance with the 3-angle machined valve job that promotes better flow, especially at low-to-mid lifts.
• Designed for 4" bore 1962-86 small block engines (302/327/350).

Visually similar to GM casting #3782461, which first appeared on the 1961 Corvette “fuelie” No accessory bolt holes, just like the original heads. Heads are sold EACH and come bare (no springs, retainers, rocker studs) Aluminum heads shave 40 lbs. off the nose of your car vs. original 461 iron heads. Improved port/chamber shape for better performance and efficiency. Standard port location for use with most intake and exhaust manifolds. 180cc intake port volume (factory 461 casting was 160cc) 62cc exhaust port volume (same as factory 461) 64cc fast-burn combustion chambers deliver big power gains vs. 461 castings. Combustion chamber volume number was calculated using an Autolite 3934 spark plug. Includes Swirl polished & undercut stainless steel 2.02” intake/1.60” exhaust valves (most 461 castings were 1.94/1.50) 3-angle valve job promotes better flow, especially at low-to-mid lifts. Intake flows 232 CFM @ .500” lift, exhaust flows 173 CFM @ .500” lift. Flow numbers were measured with a SAENZ 600 bench, 4.030 bore fixture, 1205-style intake fixture, and 28 inches of water. Exhaust port gained 20 cfm above advertised number by adding a 1-5/8 pipe (header), a larger 1-7/8 pipe flowed the same. Accepts both perimeter and center bolt valve covers. Single 1.46” diameter valve springs w/ inner damper. High nickel powdered metal valve seats provide optimum heat transfer and wear characteristics. Manganese bronze valve guides reduce friction. Valve guides are compatible with all common valve materials and fuels. Suitable for flat tappet camshafts up to .550” lift. 7 degree lightweight chromoly retainers and keepers. Hardened steel spring cups for durability. Viton positive valve seals are a modern upgrade from stock 461 castings. 3/8” chromoly screw-in rocker arm studs included. 2-piece hardened steel pushrod guide plates for use with hardened pushrods. Blocked exhaust heat riser manifold crossover port. 3/8-inch NPT coolant temperature probe port