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Vehicle Info Needed325cc Rectangle Port 24° Magnum Aluminum Cylinder Heads BB-Chevy
Ships on 01/18/2027
Lowest Price Guarantee- 325cc Rectangle Port 24° Magnum Aluminum Cylinder Heads
- BB-Chevy
- 117cc Combustion Chambers
- 1.625'' Valve Spring
- 275 lbs. Seat Pressure
- .850'' Max Lift
- 50% CNC Combustion Chambers
- Assembled
- Sold in Pairs, 2/pkg.
Big Block Chevy 325cc Rectangle Port 24° Magnum Basic Package Components 50% CNC Ported Combustion Chambers Bowl Blended Exhaust Ports Bowl Blended Intake Ports Competition 5-Angle Valve Job Intake Valve, 2.300' x 5.500' Overall Length Exhaust Valve, 1.880' x 5.442' Overall Length 1.625' OD PAC Racing Solid Roller Valve Spring, 275 lbs. on seat, .850' maximum lift, max RPM 7400-7600 10º Manley 4140 Chrome Moly 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 325cc Rectangle Port 24° Magnum Head Specifications Head Torque w/Moly Lube 75 Ft. Lbs. Rocker Stud Torque 55 Ft. Lbs. Intake Port Gasket, 1.720' x 2.450' 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 033-6850Head 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 033-6202 Suggested Manifold Edelbrock 350-2907 & 350-2927 or Brodix 158-HV2000 & 158-HV2001 Spark Plug Starting Range Champion C59C, Autolite 3932 Combustion Chambers 117cc Partially CNC Bowl Blend Intake Port Volume 325cc Partially 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.
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
AFR's 325cc Rectangle Port Powerhouse!
Are you looking for big torque and big horsepower number? AFR's BB-Chevy line of medium volume intake runners will provide you with exactly that. The phrase ''having your cake and eating it to'' would certainly be appropriate with their moderately sized intake runners producing tremendous flow figures across the entire lift range. These high flow/high velocity ports provide extreme versatility and fill the needs of many applications. From a max-effort high compression 454-605ci low rpm marine application, either one of these cylinder heads would be a great choice.
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These heads would also be ideal in a larger cubic inch ''Pro-Street'' application with their broad torque range, as well as significant rpm and horsepower capability. These heads will work best with a primary operating range of 3000-7000 rpm's (This range is an average and will vary with engine displacement as well as component selection). The 325cc comes standard with AFR's trademark .750'' (3/4'') 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. Properly selecting the correct cylinder head for an application depends on a large number of variables. 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.
325cc Rectangle Port Magnum Cylinder Head Features:
- 50% Partially or 100% Fully CNC Ported Combustion Chambers
- Bowl Blended Exhaust Ports
- Bowl Blended Intake Ports
- Competition 5-angle Valve Job
- 325cc Intake Ports
- 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
- 10° Manley 4140 Chrome Moly Retainers
- 10° Valve Locks
- 7/16'' Rocker Studs
- Adjustable 3/8'' Guide Plates
- Viton Valve Seals
- Hardened Spring Seats
- Intake Valve Seats
- Exhaust Valve Seats
- Bronze Valve Guides
