Afr 305cc Bbc Rectangle Port Cylinder Heads, Partially Ported

AFR's 305cc rectangle port heads feature partially CNC ported intake, exhaust & chambers, A356 aluminum castings and high quality components throughout. Recommended for moderate street, or street/strip builds with displacements up to 509 cubic inches, operating up to 6500 RPM. Also available with 100% CNC chambers for increased air flow (see chart). Component upgrades and machining options are available to customize AFR Heads to your specific build.
The Ultimate Race/Street Weapon!
For the ultimate in "Rectangle Port" performance, available in partial or full CNC ported, AFR 305 has no competition. With flow figures most small to medium sized rectangular port castings would be envious of, these high flowing "Rectangle" produce tremendous airspeed and really pack a punch. AFR has included it's trademark 3/4" deck, reinforced rocker stud bosses, and thick rugged castings, so you can own the strongest and most efficient heads on the market today. Premium hardware all come as standard equipment. Take note the higher flowing exhaust ports are raised .375 over stock location, and therefore these heads might not be a direct bolt-on in every application. These heads have no EGR and are not emissions legal.

Note:
1" longer head bolts needed on four bottom exhaust bolt holes. Angle mills might require a .120" Thick intake gasket.

Basic Package Components Part # 50% CNC Ported Exhaust Ports
20% CNC Ported Intake Ports
30% CNC Ported Combustion Chambers
Competition 5-angle Valve Job
11/32" Intake Valve, 2.250" x 5.500" O.A.L AFR #7620 11/32" Nail Head Exhaust Valve, 1.880" x 5.450" Overall Valve Length AFR #7630 Manley 10° Steel Retainers 1.500" O.D x 1.168" I.D x .844" I.D AFR #8518
PAC Racing Spring #1224 1.625 O.D. Solid Roller, 275lbs on seat, .850 Maximum Lift, Max RPM 7400-7600 AFR #8031
10° 11/32" Valve Locks with lashcap recess AFR #9005 ARP 7/16" Rocker Exhaust Studs AFR #6406 ARP 7/16" Rocker Intake Studs AFR #6407 Adjustable 3/8" Guide Plates AFR #6109 11/32" Viton Valve Seals AFR #6611 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 #9062 Exhaust Valve Seats 2.000" O.D x 1.580" I.D x .375" Deep AFR #9064 11/32" Intake Bronze Valve Guides .531" O.D x 2.10" O.A.L AFR #9045 11/32" Exhaust Bronze Valve Guides .531" O.D x 2.25" O.A.L AFR #9046
Specifications, Features, and Optional Supporting Components Head Torque 75 ft. lbs Intake Port Gasket AFR #6853 (.120" Thick) or AFR #6855 (.060" Thick) Exhaust Port Gasket AFR #6858 Head Gasket, Fel-Pro #1047 (Mark V and VI) AFR #6849 Head Gasket, Fel-Pro #1017-1 (Mark IV) AFR #6350 Head Bolts, ARP 135-3703 (Mark IV) AFR #6306 Head Bolts, ARP 135-3707 (Mark V) AFR #6308
Head Studs, ARP 235-4713 AFR #6307 Head Bolt Washers, Manley AFR #6320 Suggested Manifold Super Victor Victor Jr.,  Spark Plug Starting Range Autolite 3932 Combustion Chambers 121cc w/ CNC Chambers or 117cc w/ As Cast Chambers Valve Spring Pocket Diameter 1.725 O.D
Intake Port Dimension 2.380"H x 1.680"W x 11/32 Radius Exhaust Port Dimension 1.720"H x 1.920" W Valve Angle 24°/4° Intake, 15°/4° Exhaust Angle Mill
.009" per cc/ Maximum 104cc as cast or CNC Chamber Flat Mill
.006" per cc/ Maximum 108cc as cast or 114cc CNC Chamber Stud Girdle, (AFR Specific) AFR #6202 Important: Do not port match you intake manifold to any Fel-Pro gasket as it does not precisely match AFR heads.
Note: Milling head deck will affect flow numbers. 1" longer head bolts needed on four bottom exhaust bolt holes. Angle mills might require a .120 thick intake gasket.