Re: Edelbrock 600 vs. Holley Double Pumper
a 750cfm edelbrock is not equal to a 750cfm holley DP in terms of real flow (one is dry flowed, the other wet-flow tested), so you would do fine with the 750 or 800 cfm edelbrock properly jetted.
If you instead go to a Holley, forget the double pumper if driveability/ economy is a concern. Go with a 600-700cfm vacuum secondary holley. You give up little in performance, but gain a lot in driveability/ economy as I found out for myself.
1973 RS Z28: 401ci Dart Little M, Littlefield 6-71 supercharger @14lbs boost, Callies Magnum crank, Lunati rods, JE pistons, 7.8:1, AFR 227 Comp heads, T&D 1.6 shaft rockers. Reed solid FT cam (240/250@.050-.523/.542 lift-112 LSA), QFT 750 carbs