Thumpr cam question

Biggest power gain will be to ditch the eddy carb and go to a holley 650 double pumper. Put a 1" open spacer under it and call it good. A 750 can work well too, but the 650 will work better with your gearing/converter.
i hear that i hate eddy carbs,even an 1850 holley would be better.and easier to tune....