JEGS 555-514066 Small Block Chevy Aluminum Cylinder Head Features:

• For Hydraulic Flat Tappet Camshaft with 0.535 in. Maximum Valve Lift
• 78 cc Exhaust Ports
• 23-Degree Valve Angle
• Guide Plates
• Rocker Arm Studs: 3/8 in.
• Intake Port Location: Stock
• Intake Port Dimensions: 2.200 in. x 1.200 in.
• Exhaust Port Location: Stock
• Exhaust Port Dimensions: 1.356 in. x 1.420 in.
• Drilled for Standard and Vortec Intake Manifold
• Valve Cover Bolt Pattern: Dual Pattern (Perimeter and Center Bolt)
• Valve Seats Machined: Yes
• Valve Seat Machine Style: 3-Angle
• Valve Seat Material: Hardened Ductile Iron
• Valve Spring Pocked Diameter: 1.580 in. O.D. (1.600 in. O.D. Max Machining)
• Intake and Exhaust Valve Material: Stainless Steel
• Intake 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-degree
• Valve Retainers: Chromoly
• Intake Valve Guide Material: Manganese Bronze
• Exhaust Valve Guide Material = Phosphor Bronze
• Valve 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 Accessory Holes and Steam Holes
• Spark Plug Dimensions: 14 mm x 0.750 in. with Gasket Seat

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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