Pro Elite#153 CNC-Port 6-Bolt Cylinder Heads for GM LS3 Engines use the LS 6-bolt head design for compatibility with the RHS® LS Race Block, GM LSX Block and OEM 4-bolt blocks. The 6-bolt design increases clamping capacity over the factory 4-bolt configuration and improves head gasket retention, making it an excellent choice for boosted and high compression LS3 engines. These heads include an 11° valve angle and fully CNC-machined ports for better airflow. CNC-machined runners and chambers, as well as the rolled valve angle, increase overall flow capabilities, while the improved water jacket design enhances thermal conductivity. The premium .500” bronze valve guides withstand long wear while special emphasis was placed on holding precision tolerances on valve seat concentricity, allowing the valves to seal more securely for more power. The .700” thick deck and reinforced rocker rails make these cylinder heads perfect for high horsepower and boosted LS3 applications. Features .660” lift dual valve springs, chromemoly steel retainers, stainless steel intake and exhaust valves and valve seals. 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.

 54550-05SCS

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