Carb Problems, Need Help

O.k. heres the prob, i have a 73 318. the car is a little hard to start especially when its cold out. Now the big issue is keeping it running. If she hasent been running for atleast 10-15 mins then when i shift out of park or anytime i come to a stop it just drops off and shuts down like its not getting enough fuel! then i crank it back up and give it hell and it still sputters and stalls! Do i need a whole new carb or is it possibly just vacuum line probs? any help would be greatly appreciated!!! tg