AFR as cast 345cc BBC race heads

345cc As Cast w/ Parts, 119cc

AFR’s 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. Our 357 “Magnum” flows over 415 CFM @ .700 valve lift! No other production style BB Chevy head even comes close. Both of 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.Both of 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. Both the 345cc and the 357cc 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 119cc’s on the 345 “As Cast” pieces, while our fully CNC ported 357 version comes with a 121cc chamber. Both are available with an optional 114cc combustion chamber as well. 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.

Basic Package Components

Competition 5-angle Valve Job

Intake Valve, 2.300” stainless steel, AFR #7626

Exhaust Valve, 1.880” stainless steel, AFR #7631

1.550” OD Roller Dual Valve Spring with dampner, 240 lbs. on seat, .750” maximum lift, AFR #8003

10º Chrome Moly Retainers, AFR #8510

10º Chrome Moly Valve Locks, AFR #9005

Valve Seals, AFR #6611

Hardened Shims, AFR #8044

Intake Valve Seats, AFR #9062

Exhaust Valve Seats, AFR #9064

Bronze Valve Guides Intake, AFR #9045

Bronze Valve Guides Exhaust, AFR #9046

Guide Plates, AFR #6109

7/16" Exhaust Rocker Stud AFR #6406

7/16" Intake Rocker Stud AFR #6407

All Accessory Holes are Predrilled & Tapped!

Specifications, Features, and Supporting Components

Head Torque 75 Ft. Lbs.

Intake Port Gasket, 1.720” x 2.450” with 1/2” radius AFR #6855

Exhaust Port Gasket AFR #6858

Head Gasket 4.370 bore, Fel Pro #1027, AFR #6851

4.540 bore, Fel Pro #1017, AFR #6850

Mark V-VI-up to 4.500 Bore Fel-Pro #17048 or #1047

Mark V-VI-4.500 to 4.600 Bore Fel-Pro #17049

Head Bolts & Studs Standard ARP, AFR #6308, #6306, #6307

Head Bolt Washers Manley, AFR #6320

Stud Girdle AFR #6210

Sugg.. Manifold Edelbrock #2907 & #2927, AFR #5500 & #5502 Dart #6200, #6201, #6202 & #6203 Brodix HVH #2000, #2001, #2005 & #2006

Spark Plug Starting Range Champion C59C Autolite 3932

Combustion Chambers 119cc

Spring Pocket can be cut to 1.750, no deeper.

Valve Spacing Standard

Rocker Arms Standard

Valve Angle 24º/4º Intake, 15º/4º Exhaust

Angle Mill (milling available), 102cc Maximum .009” per cc

Flat Mill (milling available), 114cc Maximum .006” per cc

Note: Milling head deck will affect flow numbers.