Edelbrock Single Perf SBC 70cc Head Comp

Edelbrock introduces its new E-Street 15-degree LS3 69cc cylinder heads (PN 77618) as a premium replacement option, ensuring great power on any high-performance or stock GM LS3 engine build. These heads offer the best performance value of any aftermarket GM LS3 head. Sold in pairs and assembled with premium COMP Cams valve train components, these LS3 heads are engineered with the same architecture as the factory head, and all stock components will fit without issue. The assembled heads feature dual valve springs, chromoly steel retainers, heavy-duty stainless-steel valves, and top-quality valve seals – all inspected and assembled by qualified Edelbrock technicians. The intake valve size is 2.165 while the exhaust is 1.590 . The Beehive Valve Springs allow up to .660 lift camshafts, ideal for many mild to hot camshaft grinds. Edelbrock E-Street 15-degree LS3 cylinder heads are manufactured with premium aluminum alloy, machined to the industry’s tightest tolerances. They feature manganese bronze valve guides for extended wear, with particular emphasis placed on holding precision tolerances on valve seat concentricity. This allows the valves to seal securely, eliminating any leak-down and increasing cylinder pressures during engine operation. All Edelbrock cylinder heads feature patented Clean Cast Technology(TM) , a revolutionary 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 right out of the box. A unique dual spark-plug-pocket design allows you to use the factory-style tapered-seat spark plugs or gasket-seat spark plugs available in wider heat ranges for maximum tunability.
The E-Street Cylinder Heads for GM LS3 are designed as premium quality, bolt-on-ready cylinder heads for any high-performance or stock replacement application. The chambers are 69cc, while the dual springs allow .660 lift camshafts.

• 2.165″ Stainless Intake Valve, 1.59″ Stainless Exhaust Valve
• Sold in Pairs (2 complete, assembled heads per part number)
• Ready to bolt on out of the box
• 260cc Intake Port Volume
• GM LS3 Compatible

The Victor CNC DR-17 Oval-Port Cylinder Heads for Big-Block Chevrolet engines (PN 615467) have a larger 120cc combustion chamber designed for large displacement, high-horsepower, naturally aspirated engines running on pump gas. This design allows for a true flat-top piston configuration, promoting greater efficiency and power output.

Offered “bare,” these heads feature a 425cc port volume, 2.450″ intake valves, 1.850″ exhaust valves, raised intake and exhaust ports, and a relocated spark plug position. The raised intake and exhaust ports are particularly beneficial in maximizing cylinder fill during the valve opening cycle, while the revised spark plug location ensures a more complete combustion. Combined with optimized valve placement, these improvements result in better airflow, more power, and higher overall engine efficiency.

Each Victor CNC DR-17 cylinder head is cast at Edelbrock’s state-of-the-art foundry using premium aluminum alloy and machined in the Edelbrock Race Center in Mooresville, North Carolina. This material undergoes hot isostatic pressing (H.I.P.) to ensure a more stable and dense grain structure, which increases durability and performance. The heads feature large CNC oval ports explicitly designed to maintain high airspeed, contributing to a high torque curve throughout the engine’s operating range.

Manufactured to the industry’s tightest tolerances, these heads come fully CNC-machined, including their ports and combustion chambers. A 17° valve angle is incorporated to improve flow capability, while ductile-iron interlocking valve seats and premium manganese-bronze valve guides ensure long-lasting performance. The valve seat concentricity precision allows a perfect seal, eliminating leak-down and increasing cylinder pressure during operation. These heads are designed to be used with a shaft rocker system and can bolt directly onto standard deck blocks with a tall-deck manifold, but tall deck blocks require intake runner spacers.
Victor CNC DR-17 Cylinder Heads for Oval-Port Big-Block Chevrolet engines have 120cc combustion chambers, allowing a true flat-top piston configuration for large displacement, high-horsepower, naturally aspirated pump-gas engines.