- Engines & Components
- Cylinder Heads
- AFR Big Block Chevy 325cc Rectangle Port Magnum Aluminum Cylinder Heads
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
