Tab, naw you don't need a two barreled carb even if it would be nice. I'm running a single barrel Carter on mine. I'm not sure what model number it is.
I'm pretty sure from the sound of it your engine isn't up to par. Seems that you have checked some things already. Perhaps time to check further.
Why don't you post over on the Engine and Driveline forum and see what all is suggested.
Driving habits can vary greatly, but this sounds more like an engine problem than all driving habit problem.
Best wishes at getting to the root of the problem. Keep us posted as to what you find out.
