CARTER VS HOLLEY

HELLO! first posting,

I have a 360 Dart with a auto trans.
It currently has a Carter carb with mech secondary, no choke, which is terrible. Constant heavy black smoke when accelerating or even just tappping the gas in neutral. When you hit off the line it simply falls flat on its face and will stall. Timing ect on the money.

Is it worth redoing the carb or should I simply throw it out and install a Vac Secondary 750 Holley?

Suggestions?