Part Number: EDL-60849 Cylinder Head Style: Bare Cylinder Head Material: Aluminum Cylinder Head Finish: Natural Combustion Chamber Volume (cc): 60 CNC-Machined Combustion Chamber: No Intake Runner Volume (cc): 165cc Exhaust Runner Volume (cc): 60cc CNC-Machined Intake Runner: No CNC-Machined Exhaust Runner: No Intake Port Location: Standard Exhaust Port Location: Standard Spark Plug Style: Straight Intake Valves Included: No Intake Valve Diameter (in): 2.020 in. Exhaust Valves Included: No Exhaust Valve Diameter (in): 1.600 in. Valve Springs Included: No Damper Spring Included: No Retainers Included: No Locks Included: No Valve Stem Seals Included: No Rocker Arm Studs Included: No Rocker Arms Included: No Rocker Arm Nuts Included: No Guideplates Included: No Valve Cover Mounting Style: Centerbolt Accessory Bolt Holes Drilled: Yes Valve Guides Included: Yes Valve Guide Material: Manganese bronze Valve Seats Machined: Yes Valve Seat Machine Style: 3-angle Valve Seat Material: Ductile iron Steam Holes Drilled: No Oiling Style: Through pushrod Machined for O-Ring: No Heat Crossover: Yes Quantity: Sold individually Bolt-on power, right out of the box. All Edelbrock aluminum cylinder heads feature threaded inserts in the rocker studs and exhaust manifold bolt holes for superior strength and durability, plus hardened seats, bronze valve guides, and fully machined valve cover rails for a more consistent gasket seal. They offer improved power throughout the rpm range for greater throttle response and top-end horsepower. The intake and exhaust runners are CNC-machine profiled for superior flow and performance