AFR 24° BBC Cylinder Head 357cc Fully CNC Ported, 121cc Chambers, Competition Package

The AFR 357cc BBC Rectangle Port Cylinder Head is designed for radical "Pro Street" and racing applications with engine displacements up to 605 cubic inches, operating at or below 7400 RPM. Featuring fully CNC-machined intake runners, exhaust ports, and combustion chambers, this high-performance cylinder head is capable of flowing an impressive 425 CFM at 0.800" of lift. Titanium retainers now come standard, ensuring superior strength and durability.

Included Components

100% CNC Ported Combustion Chambers
100% CNC Ported Exhaust Ports
100% CNC Ported Intake Ports
Competition 5-Angle Valve Job
11/32" Intake Valve, 2.300" x 5.500" O.A.L – AFR #7626
11/32" Tulip Exhaust Valve, 1.880" x 5.450" O.A.L – AFR #7631
PAC Racing #1224 1.625” OD Solid Roller Dual Valve Spring – AFR #8031
10° Titanium Retainers 1.500" O.D – AFR #8507
10° 11/32" Valve Locks with Lashcap Recess – AFR #9005
ARP 7/16” Rocker Studs (Intake) – AFR #6407
ARP 7/16” Rocker Studs (Exhaust) – AFR #6406
Adjustable 3/8" Guide Plates – AFR #6109
11/32" Viton Valve Seals – AFR #6613
Hardened Spring Cup 1.740" O.D / 1.650" I.D – AFR #8046
Intake Valve Seats 2.450" O.D x 2.000" I.D x .375" Deep – AFR #9065
Exhaust Valve Seats 2.000" O.D x 1.580" I.D x .375" Deep – AFR #9064
11/32" Intake Bronze Valve Guides .502" O.D x 2.10" O.A.L – AFR #9041
11/32" Exhaust Bronze Valve Guides .502" O.D x 2.25" O.A.L – AFR #9042

357cc Competition Flow Chart

Lift (in.)	.200	.300	.400	.500	.600	.700	.800
Intake (CFM)	167	242	307	354	389	409	419
Exhaust (CFM)	135	199	249	276	288	295	305

Specifications & Features

Material: A356 Aluminum
Intake Port Volume: 357cc
Exhaust Port Volume: 135cc
Combustion Chamber Size: 121cc
Valve Angle: 24°/4° Int, 15°/4° Exh
Deck Thickness: .750"
Minimum Bore Diameter: 4.250"
Flat Mill: .006" per cc / Max 114cc
Angle Mill: .009" per cc / Max 104cc
Spark Plug Dimensions: 14mm x .750" w/Gasket Seat

Legal Notice

CARB Status: These products are illegal to operate on any public highway, road, or park. They are only legal for use on dedicated racing vehicles. Violations may result in a penalty of up to $37,500 per vehicle, revocation of DMV registration, and loss of public roadway use.