I wouldn't count on the gauge being super accurate from car to car, but it's
usefulness lies more in being comfortable with the normal pressure for a
given circumstance and recognizing a dangerous difference. Seems my old 92
when warm ran just under 30psi at idle and about 60psi at higher rpms. IIRC.

Chris
99BBB

I think at (warm) idle, the oil pressure should be between 20-30 psi.

At 3K, it should be about 50 - 60 psi.

When cold, my oil pressure gauge is pegged at 90 psi.

I asked this question a long time ago and those are the answers I got.

Also, Chris is correct, the gauges would be expected to vary a bit from
car to car.  It seems to me that seeing the needle move between idle and
higher rpms, would be a better indication that your oil pump is functioning.

I use synthetic oil in my car because I don't get to drive it as often
as I'd like, and the car can sit for weeks at a time.  Don't know if
this would have a + or - effect on the pressure reading.  I know the
viscosity characteristics should be the same, but if surface tension
variability is reduced, then the pump should be able to push the same
amount of flow at a lower pressure (since there aren't the "heavy"
components to push through the filter or other orifices).  Don't know if
this effect would be negligible (ie noticeable) or not.