It's possible the chain jumped, but you'd likely have other symptoms. Even if it did jump, fixing the timing and fuel delivery will make it easier to diagnose that.
You've replaced all the small bits, and the transmission is probably OK. That means the most likely culprit is in the timing or fuel delivery, and these are easy to work on.
Timing can be all over the place and 'run just fine'. Hell, it could be 5 degrees ATDC and with the mechanical advance coming in at higher revs it will drive pretty OK but run like poo at low revs.
Timing can also have an effect on the way things burn in the engine, and cause an exhaust stench that will cause watery eyes and smelly garages. 7psi is high, but if it fires right back up then it may not be flooded. It will be tough to tell without either an oxygen sensor setup, or the timing set correctly. See where this is headed? Timing first.
Use the piston stop to verify where the timing mark points on the balancer. Assume nothing. Searching will yield a lot of info - use the stop in both directions. Meaning turn the engine on way up against the stop, then the other. TDC will be between the two resulting marks.
Then it's simply a matter of doing what 67Dart273 said up in post #8
Also, make sure all your changes are made/done on a warm engine. Small changes are OK when cold, especially as far as timing goes. But any mixture changes, and final idle settings should occur on a FULLY warmed engine, which means 170+ degrees, better if it's at the thermostat temperature range (190+).
