This intake is designed to work with oval port BBC engines. This intake features 180° high rise design and has a 1500-6500 rpm range. The air gap design allows air to flow under the plenum to prevent heat transfer from the engine resulting in more horsepower. Intake is a dual plane square bore style and works with all 4150 Holley style carburetors. Other features include four corner water outlets, dual distributor hold down provisions, accepts late model water neck, A/C, alternator and HEI brackets.