just cant get the car to run right

Help someone give me some ideas.

73 Duster 318 2 barrel

I have replaced the distributor, and plugs and had ordered a new carb.

The old one idled fine, but put it in drive it falls on its face backfires, misses, dies etc. I got a new carb from Rock Auto, but i think the base was warped because it would idle fine, but just die when you put it in drive,

You could hold a rag around the carb and it would still run, sending that one back.

So i put the old one on again, messed around with it for a bit got it idling good, but i put in drive, and it just falls on its face if i try ti drive it. Not sure whats wrong with it.

Its timed at 10-12 degrees before TDC, and it seems to idle fine at 5-700 rpm