289/302 Dual-Plane Intake Manifold for use with 8.206-inch deck height block and inline valve heads. 4.375-inches at the front of the carburetor pad and 5.250-inches at the rear. 1500-6000 rpm range, dual plane intake and excellent fuel distribution. For use with any mid-rpm small block application, great for street cars and mild race engines. Does not fit Z or the GT-40 X heads. Installation Instructions