RHS 12333 Pro Action Small Block Chevrolet Bare Cylinder Head

RHS 12333 Pro Action Small Block Chevrolet Bare Cylinder Head

Regular price
Sale price
Regular price
Sold out
Unit price
Tax included. Shipping calculated at checkout.

RHS™ Pro Action™ Small Block Chevy 23° cylinder head, bare casting cast iron, 200cc intake runner, 50cc combustion chamber, straight plug 2.020" intake/1.600" exhaust valves
Single Cast Iron Head

Intake Exhaust
Port Volume: Intake 200cc | Exhaust 74cc
Port Dimension: Intake 1.200" X 2.180" | Exhaust 1.350" X 1.400"
Port Location: Stock
Valve Angle: 23°(stock angle ) 
Valve Head Diameter: Intake 2.020" | Exhaust 1.600"
Valve Length: 5.011" (std length + .100") 
Valve Seat Dimensions: Intake 2.120" X 1.812" X .375" | Exhaust 1.656" X 1.350" X .375"
Valve Seat Angles: Intake 35/45/60/75 | Exhaust 35/45/55/radius
Valve Guide Diameter: 11/32" 
Valve Guide Dimensions: .502" O.D. X 2.130"L X .530" boss dia. 
Valve Guide Spacing: 1.890"
Valve Guide Material: Premium bronze material for superior heat dissipation and longer life
Cylinder Head Material: Cast iron
Chamber Volume: 50cc
Spark Plug Configuration: Straight plug
Spark Plug Type: 14mm, .708" reach, 5/8" hex, taper seat style (new RHS™ castings only)
14mm, .450" reach, 5/8" hex, taper seat style (old Pro Topline castings only)
Spring Pocket Diameter: 1.55"
Pushrod Diameter: 5/16" (larger diameter will require clearancing)


Tech Notes
• Flat Milling: .006" per cc
• Angle Milling: .0075" per cc (excessive milling can cause intake manifold misalignment)
• Head Bolt Torque: Refer to cylinder head bolt manufacturer's specifications
Rocker Stud Torque: 45 lb/ft
• Intake Manifold Torque: 35 lb/ft
• Spring Pocket Machining: Can be machined to 1.625" maximum diameter, cannot be machined deeper
• Pushrod Length: Measuring with length checker (COMP Cams® #7705) required to verify pushrod geometry
• Piston to Valve Clearance: Must be verified -minimum clearance is .080" intake and .100" exhaust
• Retainer to Guide Clearance: Must always be measured when using high lift cams
• Chamber to Dome Clearance: Must always be checked with domed pistons, clearancing may be necessary
• Chamber Volume: Varies due to valve margins and dishes, should always be verified before installation
• Valve Guide Clearance: Must be checked due to the variance in valve stem diameters between manufacturers
Recommended clearance: intake .0015"-.0016", exhaust .002"-.0025"
• Header/Spark Plug Clearance: Spark plug/ wire boot clearance verification is required prior to header installation.
Minor modifications may be necessary in order to achieve proper clearance.

 Choose carefully as clearance items are not returnable for exchange or credit.

*Image is for illustration purposes only