AFR's "As Cast" Magnum Series
If "Dirty Harry" drove a racecar, it would certainly be fitted with a pair of our 345 or 357 "Magnum" cylinder heads. If huge horsepower is what you are searching for, either of these castings will certainly deliver. With our Race Ready "As Cast" 345cc flirting with 400 CFM and our fully CNC ported 357cc flowing 425 CFM, these heads represent the ultimate in airflow for your BB Chevrolet. These 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). These heads will also provide impressive torque figures at higher rpm levels. Blown, turbo, and nitrous engines will especially like the larger, higher flowing intake ports. These 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 345cc heads come standard with AFR's trademark .750" thick head deck, reinforced rocker stud bosses, and are equipped with premium one piece stainless steel 2.300" intake valves and 1.880" exhaust valves. Standard combustion chamber volume is 115cc's on the 345 "As Cast" model. 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 #
5-angle valve job
Intake Valve, 2.300" stainless steel	AFR #7626
Exhaust Valve, 1.880" stainless steel	AFR #7631
1.625 O.D. Solid Roller PAC Racing Spring, 275lbs on seat, .850 Maximum Lift	AFR #8031
10° Chrome Moly Retainer	AFR #8518
10° Valve Locks	AFR #9005
Guide Plates	AFR #6109
Viton Valve Seals	AFR #6611
Hardened Spring Cup	AFR #8046
Intake Valve Seats	AFR #9062
Exhaust Valve Seats	AFR #9064
AFR BB Chevy 7/16 Exhaust Studs	AFR #6406
AFR BB Chevy 7/16 Intake Studs	AFR #6407

Specifications, Features, and Optional Supporting Components

Head Torque	75 ft. lbs
Intake Port Gasket, 1.720" x 2.450" with 1/2" radius, Fel-Pro #1275	AFR #6856
Exhaust Port Gasket	AFR #6858
Head Gasket	AFR #6850
Head Studs	AFR #6307
Head Bolts	AFR #6308
Head Bolt Washers	AFR #6320
Stud Girdle	AFR #6210
Suggested Manifold	Dart #6200, #6201, & #6203
Suggested Manifold	Brodix HVH #2000, #2001, #2005, & #2006
Spark Plug Starting Range	Champion C59C Autolite 3932
Combustion Chambers	115cc As Cast, 121 w/ CNC Chambers
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 (Milling options available) 104cc max	.009" per cc
Flat Mill (Milling options available) As Cast 108cc max, CNC 114cc max	.006" per cc

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. Angle mills might require a .120 thick intake gasket.