carb issue?

[Rifter_Chevy]

My truck has a strange issue.

Its a 84 3/4 ton camper special SB 350 with a turbo 400 behind it, has stock rochester carb on it which i was told was just rebuilt when i bought it 6 months ago.

My issue is when i stomp on the pedal from a stop like REALLY stomp on it and depress it really fast it stalls, like just instantly dies, no sputter no beginning to pull and dieing just straight up dies, literally like i flipped the kill switch to the ignition fast. But if i press the pedal slower, like taking a full half second to fully depress it it never stalls, only when i really hit it.

Also VERY rarely when i stomp on it while already moving it will bog out at wide open throttle, this is very rare though maybe does this 2 or 3 out of every 50 times i stomp on it while moving.

Also when i start it from cold i need to help it idle for the first 10-15 seconds or it will sputter out and die but this has been normal in my experiance with alot of carbed vehicles but thought i would mention it.

Any reccomendations before i just say screw it and go buy a edlebrock 650 with a performer intake