F Head Oil Pressure

F Head Oil Pressure

My engine 1959 f head- when oil is cool at idle runs about 30 psi as the motor comes up on temp Idle oil psi go’s down to what looks like 0 on direct oil psi gage {gage is new } running SAE 30 wt oil, no clicking or knocking at idle, Is this normal or do I need to do some oil pump work,
Engine is running about 170* to 190*
Have changed oil { still using 30wt} and tried some “Lucus oil Additive “ no change.
When rpm is up oil pressure will peak at 45 to 50 psi, then back down at idle.
What say Y’all???