With a bit of work my 625cfm AVS pushes my (very) mild 383 3600lb Barracuda to 5750rpm in top gear. A 750 may have me at the top end but I bet I get away faster with the 625. I was hell bent getting a 750 on my engine some time ago but after much A/F logging & tuning I went back to the 625 for better driveability. When I upgrade the engine I will upgrade the carb as well but a 625 AVS with a few mods is all it needs for now.