Now available for the big block Chevy engine is this terrific Crosswind design manifold. It features oval ports, nitrous bosses, dual distributor holddowns and four corner water ports. This is the utlimate street manifold for 396, 427, 454 or 502 big block engines. It features a raised plenum area that allows air to pass under the plenum, producing a cooler intake charge with a resultant increase in power and torque output. Uses same gaskets recommended for above manifolds.