Afr 357cc Bbc Magnum Rectangle Port Cylinder Heads, 100% Cnc Ported, No Parts

AFR's 357cc heads feature 100% CNC ported intake, exhaust & chambers w/ no parts, A356 aluminum castings and high quality components throughout. Recommended for race applications or radical "Pro Street" builds with displacements up to 605 cubic inches. Component upgrades and machining options are available to customize AFR Heads to your specific build.
AFR's "As Cast" Magnum Series
The Original "357" Magnum BBC Cylinder Heads! If "Dirty Harry" drove a racecar, it would certainly be fitted with a pair of AFR 357cc "Magnum" cylinder heads. If huge horsepower is what you are searching for, either of these castings will certainly deliver. With our fully CNC ported 357cc flowing 425 CFM it can produce upwards of 900 HP. These cyilnder heads were targeted at larger cubic inch engines (509-632 CID) looking for maximum horsepower and rpm capability with a primary operating range of 3500-8000 rpm’s (This range is an average and will vary with engine displacement and component selection). Also, these aluminum heads provide impressive torque figures at higher rpm levels, so higher reving 450+ CIDs can benefit from the efficient runner. Blown, turbo, and nitrous engines will especially like the larger, higher flowing intake ports. AFR BBC 357cc cylinder heads will work best with camshafts exceeding .750 gross valve lift to make better use of the substantial airflow found in the higher lift range. The 357cc come standard with AFR’s trademark .750" thick cylinder head deck, reinforced rocker stud bosses, and PAC 1.625 racing springs rated to .850 lift. Standard combustion chamber volume is 121cc for our 357cc BBC and can be milled as low as 102 cc's if necessary. Properly selecting the correct cylinder head depends on a large number of variables. Please consult with one of our sales technicians to assist you in making the best decision for your particular application.

Note: Optional stud girdle required for 2° rolled valve angles and 1" longer head bolts needed on four bottom exhaust bolt holes. Longer pushrods might also be required. Basic Package Components Part # 100% CNC Ported Chambers, Exhaust, and Intake Competition 5-angle Valve Job

Specifications, Features, and Optional Supporting Components Head Torque 75 ft. lbs Intake Port Gasket AFR #6854 (.120" Thick) or AFR #6856 (.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 Full CNC Valve Spring Pocket Diameter 1.725 O.D
Intake Port Dimension 2.520"H x 1.815"W x 11/32 Radius Exhaust Port Dimension 1.780"H x 2.025" W Valve Angle 24°/4° Intake, 15°/4° Exhaust Angle Mill
.009" per cc/Maximum 104cc Flat Mill
.006" per cc/ Maximum 114cc Stud Girdle, (AFR Specific) AFR #6202 Important: Optional stud girdle required for 2° rolled valve angles and 1" longer head bolts needed on four bottom exhaust bolt holes. Longer pushrods might also be required. Note: Angle mills might require a .120" thick intake gasket.