Chevrolet SB Aluminum Cylinderheads

Cylinder Head Style: Assembled
Cylinder Head Material: Aluminum
Cylinder Head Finish: Natural
Combustion Chamber Volume (cc): 64
CNC-Machined Combustion Chamber: No
Intake Runner Volume (cc): 185cc
Exhaust Runner Volume (cc): 60cc
CNC-Machined Intake Runner: No
CNC-Machined Exhaust Runner: No
Intake Port Location: Standard
Exhaust Port Shape: Square
Exhaust Port Location: Standard
Spark Plug Style: Straight
Intake Valves Included: Yes
Intake Valve Diameter (in): 2.020 in.
Exhaust Valves Included: Yes
Exhaust Valve Diameter (in): 1.600 in.
Valve Springs Included: Yes
Maximum Valve Lift (in): 0.550 in.
Outside Diameter of Outer Spring (in): 1.460 in.
Damper Spring Included: Yes
Number of Springs Per Valve: Single
Retainers Included: Yes
Retainer Material: Steel
Locks Included: Yes
Lock Style: 7 degree
Valve Stem Seals Included: Yes
Valve Stem Seal Style: Umbrella
Rocker Arm Studs Included: Yes
Rocker Arm Nut Thread Size: 3/8-24 in.
Rocker Arms Included: No
Rocker Arm Nuts Included: No
Guideplates Included: Yes
Guideplate Pushrod Size: 5/16 in.
Valve Cover Mounting Style: Perimeter bolt
Accessory Bolt Holes Drilled: Yes
Intake Valve Angle: 23
Valve Guides Included: Yes
Valve Guide Material: Manganese bronze
Valve Seats Machined: Yes
Valve Seat Machine Style: 3-angle
Valve Seat Material: Powdered metal
Steam Holes Drilled: No
Oiling Style: Through pushrod
Machined for O-Ring: No
Heat Crossover: No
Quantity: Sold as a pair.

Notes: Designed for use with hydraulic flat tappet camshafts less than .550 in. lift. Requires use of hardened pushrods. The valve and seat combination, used in these heads, is not recommended for use with a hydraulic or mechanical roller camshaft.