- Engines & Components
- Cylinder Heads
- AFR Big Block Chevy 265cc Oval Port Magnum Aluminum Cylinder Heads
''As-Cast'' Small Port, High Velocity, Torque Monster!
Want to wake up the Big Block in your favorite tow vehicle? AFR's partially CNC ported 265cc high velocity oval port is just the ticket! They are also ideal on smaller cubic inch street performance applications (396-468ci), providing ''gobs'' of bottom end torque, tremendous throttle response, and great all around power. With AFR's trademark 3/4'' deck, reinforced rocker stud bosses, and thick rugged castings, you can own the strongest and most efficient heads on the market today. Premium hardware such as 2.19''/1.88'' one-piece stainless valves, 1.550'' double springs, 10-degree locks and retainers, and high quality studs and guideplates all come as standard equipment. 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. These heads have no EGR and are not emissions legal. .
Show More
Installation Notes: Optional stud girdle required for 2° rolled valve angles and 1'' longer head bolt needed on four bottom exhaust bolt holes.
265cc Oval Port Magnum Street Cylinder Head Features:
- 50% CNC Ported Combustion Chambers
- 40% CNC Ported Exhaust Ports (Bowl Blend)
- 80% CNC Ported Intake Ports (Bowl Blend)
- Competition 5-angle Valve Job
- 265cc Intake Ports
- 115cc Exhaust Ports (as cast)
- Intake Valve, 2.190'' x 5.460'' Overall Valve Length
- Exhaust Valve, 1.880'' x 5.448'' Overall Valve Length
- Hydraulic Roller Valve Spring: 1.550'' OD Hydraulic Roller Dual Valve Spring, 170 lbs on seat, 473 lbs @ .600'' maximum lift
- Solid Roller Valve Spring: 1.550'' OD PAC Racing Solid Roller Valve Spring, 225 lbs on seat, .680'' maximum lift
- 10° 1.450'' 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
