Cylinder Head Specifications: Combustion chamber volume: -?75cc, Intake runner, volume: -?310cc, Exhaust runner volume: -?100cc, Intake valve diameter: -?2. 19in, Exhaust valve diameter: -?1. 76in, Valve stem diameter: -?11/32in, Valve guides: -?Manganese bronze, Deck thickness: -?5/8in, Valve spring diameter: -?1. 55in, Valve spring maximum lift: -?. 700in, Rocker stud: -?7/16in, Guideplate: -?Hardened steel, Pushrod diameter: -?3/8in, Exhaust port location: -?Stock, Spark plug fitment: -?14mm x 3/4 reach, gasket seat. INSTALLATION NOTE: Match with Edelbrock head gasket sets. Bare heads will have valve guides and seats installed, but will require final sizing and a valve job to match the valves you will be using. Recommended spark plugs are Champion RC12YC or equivalent 14mm x 3/4in reach with flat gasket seat. Deck thickness: 5/8in, rocker stud diameter: 7/16in, pushrod diameter: 3/8in (width of slot in guide plate). Bare heads will have valve guides and seats installed, but will require final sizing and a valve job to match the valves you will be using. Deck thickness: 5/8in, rocker stud diameter: 7/16in, pushrod diameter: 3/8in (width of slot in guide plate).