Originally posted by R Pope
The only thing that can do what you describe is the timing chain. The distributor gear slipping won't move the timing on the damper. You're going to have to pull your front cover. Check that the chain is the right one, sounds like its too long.
Sounds like I might do that this weekend if a simpler answer doesn't prove correct by then. Maybe I can see the chain with the fuel pump removed and a flashlight?