Carter carb tuning help

Hey guys i looked around and i need help. I am a fuel injection guy and this whole V8,4BBL carb thing is driving me nuts!!!!! I rebuilt the stock carter carb for my cuda and when i brought her home it ran great. Now it runs like crap basically seems much slower and i can feel it trying to pull harder under acceleration. To me it is a fuel issue, like not getting enough. I have checked the float levels and cleaned the carb again and i am having a heck of a time getting it pull like it use to. Anyone got ay ideas?