Trick Flow GenX 255 Assembled Cylinder Head

The Trick Flow GenX 255 cylinder head is engineered for GM LS3 and LS7 engines with a 4.000" or larger bore, combining factory features with Trick Flow's race-winning technology. These heads boast fully CNC Competition Ported runners with a premium high-resolution surface finish for optimal airflow and performance potential. The valve angles are set at 12° (down from 15°) to provide increased piston-to-valve clearance and accommodate larger camshafts. Stock LS3 ports are designed to accept LS3-style intake manifolds and LS9/LSA blower assemblies. Constructed from cast aluminum, these assembled cylinder heads feature a 69cc combustion chamber volume and 255cc intake runners, with 87cc exhaust runners. They utilize a rectangular intake port shape and an oval exhaust port shape, with standard port locations. The intake valve diameter is 2.165 inches, and the exhaust valve diameter is 1.600 inches. This head includes dual valve springs rated for 448 lbs./in. with a maximum valve lift of 0.650 inches, and titanium retainers. It also includes intake valves, exhaust valves, locks, valve stem seals, and valve guides. Important fitment and installation notes: These cylinder heads are not designed as a direct stock replacement and are exclusively for 6-bolt LSX-based engines with a minimum bore diameter of 4.000 inches. They include new rocker arm rail mounts necessary for use with LS3 1.7 ratio rocker arms; OEM rocker arm rail mounts will not work with these heads. Additionally, they do not fit 2010 and later Chevrolet Camaro OEM exhaust manifolds, requiring aftermarket headers. These heads are California EO approved (E.O. #D-747) for 2007-present GM vehicles with 6.2L engines.