BTW, I think I asked this before, because it seems that's your dyno carb....what Venturi size is that 750? How about the throttle bores...what size? That means more to me than advertised CFM rating.
Carb is an untouched Holley 750 XP purchased , Sep 2016 , 1.375" venture. I flow tested it and it flowed 865-868 cfm @ 20.4 H20 dry. Funny thing is I flowed my buddy's 750 QFT old style HP zinc body with ALL the same measurements and it flows 929-931 cfm. Guess which carb made more today? J.Rob