suprtoy

I have a 641/2 with a 170cid 6cyl and I am having trouble deciding if I need a new carb or not. The car starts fine but when I step on the gas, it goes flat. If I hold the pedal at this point the engine dies. I have read about the Autolite 1100 carbs having problems with dead spots and before I invest in a new carb, I just want to know if there is anything else that could make the engine act this way. Any ideas?