just rebuilt runs bad

Yep,, tooth out would have all those symptons,, cept the tapping..

To check for tooth out on timing chain,...turn engine over by hand until you get #6 cyl valves in overlap, ie. just as the one valve closes, the other opens,, rock it back and forth, till you're sure it in dead overlap.. look at timing mark,, it should be dead on tdc,, if it's off by about 1/2 inch or more(varies with chain wear,, your's is new),, it is a tooth out.. hope it helps.. grant