No top end power, need help

A sloppy timing chain would make it stumble at low rpms and pull better on top...
Checking it its still a good idea if you have more then 16 crank degrees of slop in the chain. Its time to replace it before it leaves you stranded some day.

Reading back thru you thread you state that the snap on timing light has a tach that its idling at 3000 Rpm Are you sure about that? sound way high.