Designed for competition 396-502 big-block Chevys. # ED2902 fits rectangular-port heads and # ED2904 fits large oval-port heads (1975 & earlier). These intakes are designed to optimise the flow characteristics of an 850 cfm standard flange carb. Features include extended runner dividers, smaller plenum chambers and unique runner design for better 60 foot times and max power from 3500 to 7500 rpm. These manifolds are especially suited to 502 c.i.d. and smaller competition engines. # ED29020 is a single plane 4150 flange competition manifold designed to fit standard deck blocks from 1965 to present. This new manifold is cast with 3/8" more material in the corners of the ports for a final radius of 3/4". This extra material allows for custom port matching for use with various cylinder head applications. Victor Jr. 454-R # ED2902 will fit Edelbrock Victor Jr. # ED60409 and Victor 24-Degree # # ED77459. Made in USA