Help with Electrical Gremlin

I stole some time to work on the car. The positive connection was loose. I tightened it about a 1/4 turn.
Checked all other connections and everything looks good. All grounds are in place and good condition.
The car fires up with no problem but I am not able to keep it running before it dies out. This includes giving it throttle to about 2000 rpm.
The electrical problem has not reappeared, possible from a broken ring terminal that I replaced earlier.
Oh, and this time I did not use the Optima battery.

It seems one problem was solved and there is a new problem.

Open to suggestions?