Trick Flow® GenX® 220 Cylinder Heads for GM LS1

Transform your LS1 into a powerhouse! Trick Flow® GenX® 220 cylinder heads for GM 5.7L LS1 engines are a great value in performance. The cathedral port heads incorporate features of Trick Flow® fully CNC-ported LS heads in a more affordable "Fast As Cast®" version that flows nearly as much air as their competition ported heads. The special Fast As Cast® runner design duplicates the port shape and profile of fully CNC-ported runners, resulting in near-CNC-ported performance for the same price as regular cast cylinder heads. Other features include shallower 13.5 degree valve angles to decrease valve shrouding and increase mid-lift airflow, relocated spark plugs, CNC-profiled combustion chambers with port-to-valve seat blending (bowl blending), improved rocker arm/valve cover clearance, and a rigid casting design. Trick Flow GenX 220 cylinder heads are emissions-legal under CARB E.O. D-747 for 1997-present GM vehicles with 5.7L and 6.0L engines. They are available fully assembled or as bare castings and sold individually. Show Less