AFR 23° SBC Cylinder Head 227cc Competition Package Heads, Standard Exhaust, 75cc Chambers

AFR 23° SBC Cylinder Head 227cc Competition Package Heads, Standard Exhaust, 75cc Chambers

AFR’s 227cc “Race Ready” and “Competition” heads are engineered to deliver peak performance, featuring 100% CNC ported intake, exhaust, and combustion chambers. These heads are constructed from A356 aluminum castings and are equipped with high-quality components throughout. Designed with 60/40 valve spacing, they require shaft mount rocker arms for optimal valve train geometry, and can also be used with .050 offset intake rockers for drag race applications only.

Included Components

• 100% CNC Ported Combustion Chambers
• 100% CNC Ported Exhaust Ports
• 100% CNC Ported Intake Ports
• Competition 5-angle Valve Job
• 8mm Bead Lock Intake Valve, 2.100″ x 5.000″ Overall Valve Length
• 8mm Bead Lock Exhaust Valve, 1.600″ x 5.030″ Overall Valve Length
• PAC Racing Spring 1.550″ OD Solid Roller Dual Valve Spring, 220 lbs on seat, .710″ maximum lift, – 260* max recommended duration, Max RPM 7200-7400
• 10° Steel Retainers 1.500″ O.D x 1.120″ I.D x .705″ I.D
• 10° Bead Lock Valve Keepers with lashcap recess
• ARP 7/16″ Rocker Studs
• Adjustable 5/16″ Guide Plates
• Viton Valve Seals .600″ O.D x .495″ I.D
• Hardened Valve Spring I.D Locator 1.550” O.D x .780” I.D
• Ductile Iron Intake Valve Seats 2.200″ O.D x 1.750″ I.D x.375″ Deep
• Ductile Iron Exhaust Valve Seats 1.696″ O.D x 1.325″ I.D x .305″ Deep
• 8mm Bronze Valve Guides .502″ O.D x 2.100″ O.A.L

227cc Race Ready™ & Competition Flow Chart

227cc Race Ready™ Flow Chart:

227cc Competition Flow Chart:

*Test conducted at 28″ of water (pressure) on Superflow 1020.*

Specifications & Features

• Material: A356 Aluminum
• Intake Port Volume: 227cc
• Intake Port Dimension: 2.200″ H x 1.290″ W 5/16 Radius
• Intake Port Location: Stock
• Exhaust Port Volume: 80cc
• Exhaust Port Dimension: 1.430″ H x 1.540″ W
• Exhaust Port Location: .250″ Raised
• Combustion Chamber Size: 65cc or 75cc
• Valve Cover Bolt Pattern: Perimeter Bolt
• Valve Angle: 23°
• Valve Spring Pocket Diameter: 1.580″ O.D
• Deck Thickness: .750″
• Minimum Bore Diameter: 4.000″
• Flat Mill: .006″ per cc 60cc Maximum
• Angle Mill: .009″ per cc 55cc Maximum
• Spark Plug Dimensions: 14mm x .750″ w/Gasket Seat
• CARB Status: THESE PRODUCTS ARE ILLEGAL TO OPERATE ON ANY PUBLIC HIGHWAY. THESE PRODUCTS ARE ONLY LEGAL IF USED ON A DEDICATED RACING VEHICLE. VIOLATION ARE SUBJECT TO A MAXIMUM PENALTY OF $37,500 PER VIOLATION PER VEHICLE, REVOCATION OF REGISTRATION BY DMV, LOSS OF USE ON PUBLIC RIGHT OF WAYS AND PROOF OF CORRECTION OF THE TAMPERING.