not an a body but need some help

I say fuel filter needs changed. My Dart acted the same way after I drove it away from the place I purchased it. Turns out he bought it out of a barn and put fresh fuel in the tank and drove it to his place. I put at least four new filters on before it cleared up and now I can drive it without those problems. I should have dropped the tank and had it cleaned along with cleaning the lines from the carb to the tank. Changing the filter did the trick.

What was happening for me was I'd drive down the road and get just out of town and start to accelerate to highway speeds and it would sputter out and only allow me to run with the throttle a little over idle position. I could go a mile or two like that and try again and the same thing. I figure what was happening was the fuel bowl on the carb was going nearly dry and the filter could only let enough fuel through to support the engine at an idle or a little over.

That's my thoughts without being there to see what's up in your situation.