5.7l fwc Motor issues, any ideas on what would cause this?

[berth control]

We had one cylinder go to low pressure. 25PSI lower than the other cylinders and a bent spark plug tip. I only took the pressure after I lost power so do not know if it was that way before. Mechanic said it could have been a loose nut in the carb (that is why they use brass) bent the plug contact or the rings got so carboned up they poped off a piece of the piston. We ran the engine 3.8 V6 for 250 hours after that. Oil consumption was the same, power was the same and no vibration. We normally ran it at 3,800 RPM.

I had bad compression on an engine once too, and decided to just run it until it died. It never died, but it idled a little rough. Mine was down to 55, not 25. It was a valve issue, and I think when the engine got warm the valves started seating better. Maybe yours was also a valve issue that improved as it ran, since you didn't have any oil comsumption.