I have a 850 Proform on my race car (440 .040 over with a .557 cam) and have a Quick Fuel Brawler 750 on my street barracuda with a 360 that's .030 over with a .533 cam. No complaints on either carb, just had to adjust idle mixture screws from out of the box. They seem to run better and smoother than my old holley DP.