Designed for competition 396-502 big-block Chevys. #2902 fits rectangular-port heads and #72902 features out-of-the-box pre-assembled direct port nitrous system ready to bolt on and go! These intakes are designed to optimize 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. Victor Jr. 454-R #2902 will fit Edelbrock Victor race heads #77609 and Victor 24-degree #77409, #77459, #77429, #77479 and #77485.