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- AFR Big Block Chevy 357cc Rectangle Port Magnum Aluminum Cylinder Heads
AFR - Airflow Research 357cc Rectangle Port 24° Magnum Aluminum Cylinder Heads Big Block Chevy
033-2010-TI

Big Block Chevy 357cc Rectangle Port 24° Magnum Basic Package Components | |
100% CNC Ported Combustion Chambers | |
100% CNC Ported Exhaust Ports | |
100% CNC Ported Intake Ports | |
Competition 5-Angle Valve Job | |
Intake Valve, 2.300'' x 5.500'' Overall Valve Length | |
Exhaust Valve, 1.880'' x 5.442'' Overall Valve Length | |
1.625'' OD PAC Racing Solid Roller Valve Spring, 275 lbs. on seat, .850'' maximum lift, max RPM 7400-7600 | |
10º Titanium Retainers | |
10º Valve Locks | |
7/16'' Rocker Studs | |
Adjustable 3/8'' Guide Plates | |
Viton Valve Seals | |
Hardened Spring Seat | |
Intake Valve Seats | |
Exhaust Valve Seats | |
Bronze Valve Guides | |
Big Block Chevy 357cc Rectangle Port 24° Magnum Head Specifications | |
Head Torque w/Moly Lube | 75 Ft. Lbs. |
Rocker Stud Torque | 55 Ft. Lbs. |
Intake Port Gasket, 1.775'' x 2.500'' with 1/2'' radius | Fel-Pro 375-1275 - DO NOT PORT MATCH Intake Manifold to Fel-Pro Gasket. |
Exhaust Port Gasket | AFR 033-6858 |
Head Gasket Mark IV | 4.540'' Bore, Fel Pro 375-1017 AFR 033-6850 |
Head Gasket Mark V - VI | Up to 4.500'' Bore, Fel Pro 375-1047 |
Head Gasket Mark V - VI | 4.500'' to 4.600'' Bore, Fel Pro 375-17049 |
Head Bolts & Studs | Standard ARP |
Head Bolt Washers | Manley Standard |
Stud Girdle | AFR 033-6210 |
Suggested Manifold | Edelbrock 350-2907 & 350-2927 or Brodix 158-HV2000 & 158-HV2001 |
Spark Plug Starting Range | Champion C59C, Autolite 3932 |
Combustion Chambers | 121cc Fully CNC'd |
Intake Port Volume | 357cc Fully Ported |
Exhaust Port Volume | N/A |
Spring Pocket can be cut to 1.750, no deeper. | |
Valve Spacing | Standard |
Rocker Arms | Standard |
Valve Angle | 24° / 4° Intake ; 15° / 4° Exhaust |
Angle Mill, 104cc Maximum | .009'' per cc |
Flat Mill, As Cast 108cc, CNC 114cc Maximum | .006'' per cc |
NOTE: | Flat and Angle mills might require a .120'' thick head gasket. |
Specifications:
AFR's 357 MAGNUM...The Name Says It All.
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, this castings will certainly deliver. With the fully CNC ported 357cc flowing 425 CFM it can produce upwards of 900 HP. This cyilnder head was targeted at larger cubic inch engines, 509-632ci, 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+ cubic inches 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'' (3/4'') thick cylinder head deck, reinforced rocker stud bosses, premium one-piece stainless steel 2.300'' intake valves and 1.880'' exhaust valves. Standard combustion chamber volume is 121cc for the 357cc BBC and can be milled as low as 102 cc's if necessary. Take note the higher flowing exhaust ports and bolt pattern are raised .375'' (3/8'') over stock location, this rarely affects header or chassis fitment. .
Installation Notes: Optional stud girdle required for 2° rolled valve angles and 1'' longer head bolt needed on four bottom exhaust bolt holes. Longer pushrods may also be required.
357cc Rectangle Port Magnum Cylinder Head Features: ![]() |
What would be the smallest cu in to best use these heads,at present have 540, I’m thinking 565
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