AFR Heads, 3670 BBC AFR 300 Magnum Heads, CNC Ported, Hydraulic Roller, 112cc

AFR 300cc port heads are recommended for agressive street, street/strip or race big block Chevy's with displacements up to 540 cubic inches operating at or below 6800 RPM. The 300cc oval port cylinder heads feature 100% CNC machined intake runners, exhaust ports and combustion chambers; our 300cc oval port flows 388 CFM at 0.700" lift and is the ultimate street/race weapon without having to step up to a rectangular port design

100% CNC Ported Exhaust Ports

100% CNC Ported Intake Ports

100% CNC Ported Combustion Chambers

Competition 5-angle Valve Job

11/32" Intake Valve, 2.300" x 5.500" O.A.L

11/32" Nail Head Exhaust Valve, 1.880" x 5.450" Overall Valve Length

PAC Racing #1940 1.550" OD Hydraulic Roller Dual Valve Spring 175 lbs. on seat, .725" maximum lift, Max RPM 6500-6700

Manley 10° Steel Retainers 1.500" O.D x 1.120" I.D x .705" I.D

Manley 10° Steel Retainers 1.500" O.D x 1.168" I.D x .844" I.D

10° 11/32" Valve Locks with lashcap recess

ARP 7/16" Rocker Exhaust Studs

ARP 7/16" Rocker Intake Studs Adjustable 3/8" Guide Plates 11/32" Viton Valve Seals Hardened Valve Spring I.D Locator 1.550" O.D x .780" I.D Intake Valve Seats 2.450" O.D x 1.950" I.D x .375" Deep Exhaust Valve Seats 2.000" O.D x 1.580" I.D x .375" Deep 11/32" Intake Bronze Valve Guides .502" O.D x 2.10" O.A.L 11/32" Exhaust Bronze Valve Guides .502" O.D x 2.25" O.A.L