Stalling issue!

I have a 454 bored .30 over with a Holley 750 cfm carb. My issue is stalling at low rpms. The car idles fine and drives great however, when I come to a stop or slow down the car stalls. It also has a slight hesitation when accelaerating at around 3500 rpm. I rebuilt the carb and still having the same prob. I have a Holley 110 gph mechanical pump on now. Should I change to a 130 or 170 gph to let more fuel in? Any ideas would help......I cleaned my earls fuel filter and it seemed fine.........