AFR 23° SBC Cylinder Head 227cc Race Ready Heads, Spread Port Exhaust, 75cc Chambers

The AFR 227cc SBC Race Cylinder Head is designed for high-performance applications, featuring 100% CNC-ported intake, exhaust, and combustion chambers. Built from premium A356 aluminum castings, these heads incorporate top-tier components for maximum durability and performance. With 60/40 valve spacing, they require shaft mount rocker arms for optimal valvetrain geometry but can be used with .050 offset intake rockers for drag race-only applications.

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" – AFR #7256
8mm Bead Lock Exhaust Valve, 1.600" x 5.030" – AFR #7254
PAC Racing Spring 1.550" OD Solid Roller Dual Valve Spring – AFR #8000
10° Steel Retainers 1.500" O.D x 1.120" I.D x .705" I.D – AFR #8511
10° Bead Lock Valve Keepers with lashcap recess – AFR #9009
ARP 7/16" Rocker Studs – AFR #6405
Adjustable 5/16" Guide Plates – AFR #6103
Viton Valve Seals .600" O.D x .495" I.D – AFR #6612
Hardened Valve Spring I.D Locator 1.550” O.D x .780” I.D – AFR #8048
Ductile Iron Intake Valve Seats 2.200" O.D x 1.750" I.D x.375" Deep – AFR #9060
Ductile Iron Exhaust Valve Seats 1.696" O.D x 1.325" I.D x .305" Deep – AFR #9070
8mm Bronze Valve Guides .502" O.D x 2.100" O.A.L – AFR #9051

Flow Bench Results

Tested at 28" of water pressure on a Superflow 1020.

227cc Race Ready™ Flow Chart

Lift	.200	.300	.400	.500	.550	.600	.650	.700
Intake	148	210	261	296	304	312	315	318
Exhaust	116	155	204	220	225	229	233	237

Technical Specifications

Material: A356 Aluminum
Intake Port Volume: 227cc
Exhaust Port Volume: 80cc
Combustion Chamber Size: 65cc or 75cc
Valve Angle: 23°
Deck Thickness: .750"
Minimum Bore Diameter: 4.000"
Spark Plug Dimensions: 14mm x .750" w/Gasket Seat

Legal Disclaimer

CARB Status: THESE PRODUCTS ARE ILLEGAL TO OPERATE ON ANY PUBLIC HIGHWAY. THEY ARE ONLY LEGAL IF USED ON A DEDICATED RACING VEHICLE. VIOLATIONS MAY RESULT IN FINES UP TO $37,500 PER VEHICLE, REGISTRATION REVOCATION, AND OTHER PENALTIES.