The RHS Single Plane 23° Aluminum Intake Manifold is engineered specifically to port match fit RHS® Small Block Chevy cylinder heads. Additionally, this manifold is the only one designed with bolt machining to fit all versions of Small Block Chevy cylinder heads, including classic originals, Vortec GM heads and late model perimeter corner vertical bolt style crate engine heads. It provides the power and strong torque curve throughout the mid-RPM range that is required for performance street, circle track and drag race applications up to 434c.i. The manifold also features auxiliary water ports, integral water crossover and dual sided distributor mounting points. Female pipe fittings at all four corners allow external water lines for reverse cooling applications.