Which carb will get me the most performance from my corvette?

[Billy M]

I have a 1979 corvette and currently the carb on it is bad. It is a Holley Quadrajet 650 cfm double pumper with vacuum secondaries. I dont no what exactly is wrong with it but the vacuum secondaries do not work and when you go to adjust the carb with the screws on the side nothing happens. Anyway, this guy offered me a brand new Edelbrock 750 cfm carb. Its not a double pumper but it has only 5 minutes of use. Im wonder as far as performance goes what would give me more, a carb with 650 cfms that is a double pumper, or a carb with 750 cfms with no double pumper?

 

[Sunny]

A working 750cfm carb is better for performance than a non working 650 .
750CFM is pretty overkill for a 350 though, if it's stock.