when u ramp up on the throttle u are really in ur primary side of ur carb when u punch it u are in the primary and sec. sides of ur carb meaning more fuel. sounds like ur primary is a lil lean and since it is an edlebrock carb some tuning as thesals mentioned will do wonders but remember ignition timing and fuel delivery give the same excact symptoms so set ur timing. if u dont have access to a timing light this the way i do it. turn the distributor counter clock wise till it sounds like the motor starts to pick up on the idle like it frees up but if ur already at that point turn it clock wise till it starts to idle down and do the counter clock wise again until it sounds like it frees up that is max vacuum right there then try running it again and then go for the carb tuning. may sound dumb but thsi is how i set all my ignitions never have a problem