Edelbrock Performer D-Port Complete 87cc

Intended for installation on 1965-1976 Small-Block Oldsmobile 350-403 c.i. engines equipped with a flat tappet camshaft, these 356-T6 aluminum casting cylinder heads (PN61039) are a modern refinement to our PN6051 heads, except they can accommodate a factory-style mechanical fuel pump. A smaller 68 cc combustion chamber achieves a more appropriate small block compression ratio compared to our PN61025/61029’s larger 77 cc chamber, which yields a lower compression ratio than most engine builders desire on a small block engine. These heads require a 3.9375” minimum bore and feature a modern chamber design with optimized spark plug positioning. Maximum airflow is achieved through the factory 6-degree valve angle using high-flow 200 cc intake and 130 cc exhaust port volumes, along with 2.072” intake and 1.680” exhaust valve sizes in their O.E. positions. A finished deck thickness with added material above the intake port and pre-counterbored head-bolt holes for .5” diameter studs provide extra clamping force in key areas. A stud-and-guide plate valvetrain system (as opposed to the O.E. pedestal type) provides a solid foundation for the beefier diameter pushrods, and Helicoil inserts in the exhaust and rocker stud holes keep bolts secured. However, there are no provisions for a heat crossover. Although these heads will fit on Big-Block Oldsmobile engines, the 68-cc combustion chamber size is not ideal for a big-block application as it will raise compression. See PN 61025 and PN 61029 for big-block specific cylinder heads.
For 350-403 c.i. Olds engines with a flat tappet cam, these heads are made of 356-T6 aluminum with 68 cc chambers, high-flow 200 cc intake and 130 cc exhaust port volumes, and 2.072” intake and 1.680” exhaust valve sizes.
356-T6 Aluminum Casting, 68cc Combustion Chamber Volume, 200cc Intake Port Volume, 130cc Exhaust Port Volume, 2.072” intake & 1.680” exhaust valve sizes, 3/8” dia. Pushrod diameter, 5/8” Finished Deck Thickness

• Retains compatibility with OEM and popular aftermarket manifolds and Headers
• Maximum compatibility with OEM and aftermarket components
• Allows the use of an “OEM” style mechanical fuel pump
• Mechanical Fuel Pump Clearance Cutout
• Factory 6-degree valve angle
• OEM Port Locations

The Edelbrock Victor CNC 12 6-Bolt Head for GM LS7 291cc/69cc Individual #77668 is designed for maximum effort naturally aspirated and boosted applications. It features .220 raised intake runners and .100 raised exhaust ports that provide a better line of sight into the cylinders and allow for an improved short turn. The raised intake runner design fits both stock and aftermarket LS7 intake manifolds and can be used with stock or aftermarket valve trains. The head utilizes the GM LS 6-bolt design, making it compatible with the GM LSX block and all aftermarket iron or aluminum 6-bolt per cylinder LS race blocks. The 6-bolt design offers increased clamping capacity over the standard factory 4-bolt configuration and improves head gasket sealing – ideal for high compression naturally aspirated engines and high boost applications. Features include a 12-degree valve angle and fully CNC-machined ports for maximum airflow. CNC-machined runners and chambers, as well as the .220 raised intake ports and 12-degree valve angle, increase overall flow capability, while a revised water jacket design enhances thermal conductivity and tunability. The manganese bronze valve guides withstand long wear with emphasis placed on holding precision tolerances on valve seat concentricity, allowing the valves to seal securely, which eliminates leak down and increases cylinder pressure during engine operation. Finally, the .700 thick deck and .400 raised valve cover rail make this head ideal for maximum horsepower and high valve lift applications. All Edelbrock Victor CNC heads feature patented Clean Cast Technology(TM) , a process that eliminates casting flaws and promotes a smoother internal surface finish for greater air and coolant flow. These benefits provide more power and increased cooling ability. Part #77668 is a bare head that features: 307cc runners, 69cc chambers, 2.250 intake/1.615 exhaust valves, CI PM valve seats and no down nozzles.
The Edelbrock Victor CNC 12 6-Bolt Head for GM LS7 291cc/69cc Individual #77668 is specifically designed for maximum effort naturally aspirated and boosted applications.

• Premium 110 BHN aluminum alloy, .220″ raised intake port, .100″ raised exhaust port, Copper valve seats, 307cc or 291cc intake port volume, 2.250″ or 2.200″ x 1.615″ valve job