A-Team Performance 1903 Remanufactured Rochester Quadrajet Carburetor 750 CFM – 4MV – Compatible with 1975-1985 Hot Air Style Choke Carb GM/Chevy Remanufactured 4-bbl. Carburetor Q-Jet Casting 750 CFM Vacuum Secondary Electric Choke 1975-85 305-454c.i. Calibration Direct replacement-style performance carburetors that outperform “over-the-counter” O.E. style replacement carbs. Our Universal Performance carburetors improve throttle response and overall performance throughout the RPM range. Each carb has a distinctly different fuel curve calibrated for a particular application.