A 750 dominator is the same as a 750 double pumper in airflow, but a completely different carb since it's a dominator based carb. They use skirted boosters to kill airflow through the carb. It's calibration is in need of rework, as they weren't very good. So to answer your question, you'd be better off with a standard 4150 carb over the dominator, but it's still going to have to be calibrated for your combo.