650 / 750 Double pumper Holley

gunmetal1 said
I currently have a 670 Street Avenger on my car (340 challenger, 727 tranny 410 gears) and am looking to change it out to a double pumper. I can buy a new carb but that will cost a fortune, I've never rebuilt one and am looking for a good core to start with. I just installed my first transmission and it's got me wanting to do more by myself. I've got a friend who will help me with the rebuild. I want something that I made not store bought. 650 or 750 cfm.
Anyone got anything thats not being used that can help teach and old dog new tricks?

I've got a Strange Spool for a 8 3/4 489 case I'd be willing to deal with. 32 spline I think.

Someone out there correct me if I'm wrong but I was under the impression that the old double pumpers 650/750 were wet flowed and that by today's standard they fall short of the advertised cfm, the newer carbs like the Avenger are close to actual flow numbers. So what I'm saying is that the 750 DP might only flow as much as your 670 Avenger so the only advantage is the mechanical secondary. Incidentally, I have heard that the Avenger will get 5 miles more to the gallon than a traditional Holley carb, If you plan on getting rid of it I could be interested??