360 driveability problem

If you're new timing set has the 3 keyway's in it you could try the cam in the advanced spot. Advancing a cam will give you more low end power. I would also use a degree wheel and see were your can is at now and when you advance it. Like Adam says it may be more cam than you think. Or it could be mis-ground, checking it with a degree wheel will tell you what you have. I'm thinking it is a camshaft problem given the problems you list and the things you have already tried.

Chuck