Engine Oil Pressure

[gearhead46]

I rebuilt the engine in my 65 GS a few years ago after I found the "new to me" car had been rode hard and put away wet.  There were 3 rod bearings that were just about to spin due to a broken cam sprocket that left nylon debris in the engine and was not cleaned out after the sprocket was replaced.

I drove the car for maybe a few hundred miles and was not comfortable with only have idiot lights for engine monitoring.  I bought a set of gauges at a swap meet and installed them.  I am finding that my oil pressure is only about 30psi cold and goes to about 10 when it is hot.  I am not leaking oil anywhere or have any indication I left out that rear main gallery plug.  I know my way around engines having built many of them over the  years, so I am not thinking I did anything wrong.

What should I expect for oil pressure? I was anticipating around 50 or so and maybe 35 hot.  My first thought is that it is the gauge that I put in.  It is not a SW or Autometer package and I'm not comfortable that its of high quality.  I plan to check it out with a mechanical gauge, but haven't gotten around to it yet. 

[425BUICK]

I built a 425 about 40 years ago and it was with a factory fresh block.  Mains were about .0025 if I remember right.  It has run 40 lbs cold or hot ever since, and about 12 hot at idle, maybe 15 cold.  Just built another one.  Mains were about .003 on this on.  So far, oil pressure is about 2-3 lbs less than the first one.  The engine doesn't seem to care.  I don't race or abuse them.  Someone with more performance experience could probably give you more info.

Tom