Which Carb Gives a Balance of Power & MPG?

There called (Around here at least) divided single planes, which I'm sure you have heard before. There low rise runners are much like the older MoPar single plane intakes, like the 273 units. I think a guy has one for sale here now....

I'd like to see the Offy with a decent raise to the runners myself. I know what you mean, your description about being very open under the carb. It's like a long tunnel with the intake runners coming into it rather than the intake runners going to the carb.