AFR 24° BBC Cylinder Head 385cc Fully CNC Ported, 121cc Chambers, Competition Package

The AFR 385cc BBC Rectangle Port Cylinder Head is our largest and best flowing 24° big block Chevy cylinder head, designed for serious high-performance applications. Featuring fully CNC-machined intake runners, exhaust ports, and combustion chambers, these heads are optimized for +540 cubic inch racing engines operating at or below 7600 RPM. Equipped with titanium retainers and premium components, these heads are capable of flowing an impressive 456 CFM at 0.900" of lift.

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, 2.350" x 5.500" O.A.L (AFR #7627)
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 Retainer 1.500" O.D x 1.180" I.D x .765" I.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)

Performance Flow Data (Tested at 28" of Water on Superflow 1020)

Bore Size: 4.600", Intake 3/4" Radius Plate Exhaust, 2 1/8" Curved Pipe

Lift	.200	.300	.400	.500	.600	.700	.800	.900
Intake (CFM)	169	249	312	359	411	428	439	449
Exhaust (CFM)	139	190	245	280	299	309	315	321

Specifications & Features

Material: A356 Aluminum
Intake Port Volume: 385cc
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/ Maximum 114cc
Angle Mill: .009" per cc/Maximum 104cc
Spark Plug Dimensions: 14mm x .750" w/Gasket Seat

Legal Disclaimer

CARB Status: THESE PRODUCTS ARE ILLEGAL TO OPERATE ON ANY PUBLIC HIGHWAY. THEY MAY ONLY BE USED ON DEDICATED RACING VEHICLES. VIOLATIONS MAY RESULT IN FINES UP TO $37,500 PER VEHICLE, DMV REGISTRATION REVOCATION, AND LOSS OF USE ON PUBLIC ROADWAYS.