Remove a variable...Maybe a friend can let you borrow a carburetor that runs on their car and doesnt have problems...Once you have that squared away, move on to another variable. Do you have a fuel gauge maybe?

Apples to Oranges. My Dart used to do that when I first got it..but it was a 1bbl carb. moving up to a 2bbl improved but the 4bbl woke it up quite a bit.

What kinda carb you got on there? maybe a power valve is blown? You are leaking excess fuel into your manifold?