With your car is warmed up and running take a flash light and look down the bores. You should not see any gas dripping. It has been my experience that every "new" carb needed a fresh rebuild as in every one dripped.. I also could never get a Holley to work worth a flip on my Bird.
If you don't have a flooding problem then you most likely need to tweak the carb for your application..power valve jets and such.