Designed for high-output, small-block competition engines, the Victor 23° High-Port CNC heads are ideal for applications that require higher flow levels than those available from standard port heads. Fully CNC-ported by Mike Chapman and his team of expert machinists, these heads have 71cc combustion chambers and come in three intake port sizes. The valve cover rail is raised .600' and the rocker arm minimum offsets are: Intake .350' with zero offset on the exhaust side. These heads require intake and exhaust valves that are +.200' longer than stock or if 1.980' or taller valve spring height is maintained, use .300' longer than stock valves. Match these heads with Victor Series High-Port manifolds for maximum, proven performance and a winning combination.