Designed for 1965-79 Pontiac 326-455 c.i.d. V8s (except Ram Air V and 265/301 V8s). Provides great throttle response for performance you can feel. #2156 is stock replacement/ street legal part for 326, 350, 389, 400 and 455 V8s with OEM 4-bbl. carb.; 1966-72 (1973 non-CA); except stock equipped EGR.