Chevy LS3 Rectangle Port Bare Aluminum Cylinder Head 255cc/72cc E42006. This product data sheet is originally written in English. Bous Performance aluminum cylinder heads offer horsepower, torque and performance that your LS engine is capable of achieving. Features a raised rocker rail for improved rocker arm/valve cover clearance. Our cylinder heads have been carefully designed to achieve the economic growth from a cylinder head right out of the box, and yielding larger capabilities of port velocity with potential of more flow volume with intake and exhaust runners, with room for a CNC program that blends the bowls and Port matching the for greater forced induction of our cylinder heads throughout…