It was dropping to just above the red zone on the dash guage. I haven't been able to get a mechanical unit in there yet. Before I installed the engine (see my 1st post - Oil pressure problems - 93 Regal 3.8
) I replaced the oil pressure relief valve but did not replace the spring. Assuming that it might be weakened in some way I have ordered a new one. (Actually I ordered 10 of them because that'* the only way the GM parts guy could get them. If anyone needs one let me know. They're only about $1.20 each.)
The approach here is to eliminate all possible problems. Maybe the old spring was weaker in some way, or shorter, and a new one will get the pressure back up to where it needs to be. If that doesn't work I'll try Dan'* shimming approach. If that doesn't work then I'm up the creek.
To add to all that, sitting in the parking lot idling last night I picked up the faint sound of what is probably the rod beginning to knock. So the car is off the road until I mess around trying to get the oil pressure up to where it needs to be.
The engine is used and bought to replace the original one which died a while back. The rod journals looked to be in pretty good shape but I replaced the rod bearings. The one main bearing I inspected also appeared to be in pretty good shape so I didn't check the rest of them. Probably one of the others is bad and may be the cause of my low pressure, assuming the greater clearance from a really worn main journal/bearing would cause that. So I guess if I can't get the pressure up to where it needs to be I'm looking at a crank kit.
Comments, suggestions, etc. will be appreciated.