AFR Heads, 3680 BBC AFR 300 Magnum Heads, CNC Ported, Solid 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 Spring #1224 1.625 O.D. Solid Roller, 275lbs on seat, .850 Maximum Lift, Max RPM 7400-7600

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