Aluminum Cylinder HeadSmall Block Chevy195 cc Intake Ports64 cc Combustion Chamber2.020 in. Int. Valves1.600 in. Exh. ValvesStraight Spark Plug StyleFor Hydraulic Flat Tappet Cam0.535 in. Max. LiftSold Individually JEGS 555-514063 Small Block Chevy Aluminum Cylinder Head Features:For Hydraulic Flat Tappet Camshafts with up to a .535 Maximum Valve Lift76 cc Exhaust Ports23-Degree Valve AngleGuide PlatesRocker Arm Studs: 3/8 in.Intake Port Location: StockIntake Port Dimensions: 2.080 in. x 1.270 in.Exhaust Port Location: StockExhaust Port Dimensions: 1.380 in. x 1.420 in.Drilled for Standard and Vortec Intake ManifoldValve Cover Bolt Pattern: Dual Pattern (Perimeter and Center Bolt)Valve Seats Machined: YesValve Seat Machine Style: 3-AngleValve Seat Material: Hardened Ductile IronValve Spring Pocked Diameter: 1.580 in. O.D. (1.600 in. O.D. Max Machining)Intake and Exhaust Valve Material: Stainless SteelIntake Valve Head Diameter: 2.020 in.Intake Valve Stem Diameter: .3415 in.Intake Valve Length: 5.115 in.Exhaust Valve Head Diameter: 1.600 in.Exhaust Valve Stem Diameter: .3415 in.Exhaust Valve Length: 5.115 in.Valve Locks: 7-degreeValve Retainers: ChromolyIntake Valve Guide Material: Manganese BronzeExhaust Valve Guide Material = Phosphor BronzeValve Guides: 1/2 in. O.D.Valve Guide Length: 1.950 in.Valve Guide Clearance: .0014 in. - .002 in. (with .3415 in. diameter valve stem)Drilled for AccessoriesSteam Holes are not Drilled in this HeadSpark Plug Dimensions: 14 mm x 0.750 in. with Gasket Seat