best carb for 340?

I'm running a Holley 770 Street Avenger on my 340. Stock bore, Eddy heads & intake, .488" lift cam, Full 2.5" TTI exhaust, 4spd w/3.55's .... I have been contemplating trying a smaller carb to see how it performs .. The car runs GOOD now, but curious if a smaller cfm carb will help or hurt..