AFR BBC 357 Magnum Aluminum Cylinder Heads

Sale: $3,481.40
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AFR 357cc Fully CNC Ported Magnum BBC Cylinder Heads

AFR’s Magnum Series


BBC 357cc Fully CNC ported Cylinder Heads
Click to enlarge

If “Dirty Harry” drove a racecar, it would certainly be fitted with a pair of our 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). As well, 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, PAC 1.625 racing springs rated to .850 lift, and are equipped with premium one piece stainless steel 2.300” intake valves and 1.880” exhaust valves. 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.




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.(see footnotes here)

AFR 357cc BBC CNC Aluminum Cylinder Head Flow Chart

357 BBC Cylinder Head Flow Chart


Basic Package Components
100% CNC Ported Intake Ports, Exhaust Ports, and Combustion Chamber
Competition 5-angle Valve Job
100% CNC Ported Chambers, Exhaust, and Intake
AFR #7626Intake Valve, 2.300" stainless steel
AFR #7631Exhaust Valve, 1.880" stainless steel
AFR #80311.625 O.D. Solid Roller PAC Racing Spring #1224, 275lbs on seat, .850 Maximum Lift
AFR #851810° Chrome Moly Retainer
AFR #900510° Valve Locks
AFR #6109Guide Plates
AFR #6611Viton Valve Seals
AFR #8046Hardened Spring Cup
AFR #9062Intake Valve Seats
AFR #9064Exhaust Valve Seats
AFR #9045Bronze Valve Guides Intake
AFR #9046Bronze Valve Guides Exhaust
AFR #6406AFR BB Chevy 7/16 Exhaust Studs
AFR #6407AFR BB Chevy 7/16 Intake Studs


Specifications, Features, and Optional Supporting Components
75 ft. lbs.Head Torque
AFR #6856Intake Port Gasket, 1.720" x 2.450" with 1/2" radius, Fel-Pro #1275
Important: Do not port match your intake manifold to Fel-Pro gasket as it does not precisely fit AFR heads.
AFR #6858Exhaust Port Gasket
AFR #6850Head Gasket, Bore 4.540 Fel-Pro #1017
Mark V-VI-up to 4.500 Bore Fel-Pro #17048 or #1047Head Gasket
Mark V-VI-4.500 to 4.600 Bore Fel-Pro #17049Head Gasket
AFR #6306Head Bolts
AFR #6307Head Studs
AFR #6308Head Bolts
AFR #6320Head Bolt Washers
AFR #6210Stud Girdle
AFR #5500Suggested Manifold
Edelbrock #2927Suggested Manifold
Dart #6200, #6201, & #6203Suggested Manifold
Brodix HVH #2000, #2001, #2005, & #2006Suggested Manifold
Champion C59C Autolite 3932Spark Plug Starting Range
121ccCombustion Chambers
Can be cut to 1.750, no deeperSpring Pocket
StandardValve Spacing
StandardRocker Arms
24°/4° Intake, 15°/4° ExhaustValve Angle
.009" per ccAngle Mill (milling options available), 104cc Maximum
.006" per ccFlat Mill (milling options available), 114cc Maximum

Note: Milling head deck will affect flow numbers. Angle mills might require a .120 thick intake gasket.

Add to Cart:

  • Model: 2010
  • Shipping Weight: 94lbs