just got a 74 valiant. it idles ok but when you give it gas it sputters or chokes

Sounds like the timing is off or the accelerator pump is bad. WHen you open the throttle and look in the carb, do you see gas squirting in? If not it is probably the accelerator pump. Check timing and also see if the vacuum advance is working.

How does it run with the choke flap partly closed?
It could be a small vacuum leak causing an overall lean condition when you try to accelerate.

Check / replace all the vacuum hoses and make sure the PCV valve is functioning. (not stuck wide open or cracked) Check to be sure the Intake manifold and carb. mounting bolts are all tight.
DD