RHS® Pro Elite™ CNC-Port 6-Bolt Cylinder Heads for GM LS3 Engines

RHS® introduces its new Pro Elite™ CNC-Port 6-Bolt Cylinder Heads as a premium LS3 performance head, ensuring great power on high horsepower and boosted engine builds.

RHS® Pro Elite™ CNC-Port 6-Bolt Cylinder Heads for GM LS3 Engines utilize the popular LS 6-bolt head design, making them compatible with the RHS® LS Race Block, GM LSX Block and OEM 4-bolt blocks. The 6-bolt design offers increased clamping capacity over the standard factory 4-bolt configuration and greatly improves head gasket retention, ideal for boosted and high compression engines.

These heads are manufactured with premium materials and machined to the industry’s tightest tolerances. Features include an 11° valve angle and fully CNC-machined ports for improved airflow. The CNC-machined runners and chambers, as well as the rolled valve angle, increase overall flow capability, while the revised water jacket design enhances thermal conductivity. The premium .500” bronze valve guides withstand long wear with particular emphasis placed on holding precision tolerances on valve seat concentricity, allowing the valves to seal securely for more power. Finally, the .700” thick deck and reinforced rocker rails make these cylinder heads ideal for high horsepower and boosted LS3 applications.

Available bare or assembled – assembled versions feature .660” or .700” lift dual valve springs, retainers, intake/exhaust valves and valve seals – all inspected and assembled by qualified RHS® performance technicians. See the application chart below for cylinder head specs and other assembly components.

All RHS® cylinder heads feature patented Clean Cast Technology™, 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 cooling, right out of the box. 

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About RHS®

Founded in 1967, Racing Head Service® began exclusively as a manufacturer of racing cylinder heads. Over the years, RHS® grew into an integrated racing company, offering complete turn-key engines and race car parts via mail order. With innovative cylinder head designs and porting techniques, the company became a performance icon in both circle track and drag racing.

RHS® is now a proud member of the COMP Performance Group™ with the industry’s largest and most advanced airflow technology team that produces both aftermarket cylinder heads and engine blocks. For more information about RHS® and its products, visit us online at www.racingheadservice.com or call us at 1.877.776.4323.

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