Joe;
I'm sure every engine is different,but this is what I have found with mine concerning idle
oil pressures....
For normal everyday use I had my idle rpm set at about 750rpms..... Normal driving,everything fully warmed up idling at 750rpms,
oil pressure normally around high 20's to low 30's psi....I also have a warning light hooked up in conjunction with my mechcanical
oil pressure gauge,light is set to go on at 20 psi....
When running on the track for the first time after a 10 lap session at 1.3 miles per lap,came of the track and the oil light was on,very scary,looked at the gauge showing just on or under 20 psi.....I revved the motor a little,maybe up to 1200 rpms,light goes off,oil pressure goes up to 35 psi,got in the pits,checked the oil temp,(gauge is under the hood),oil temp on 210..... Next session out oil pressure back to normal,run the session,same things happens.....so now I idle it up to 900 rpms and go out again,after another 10 lap session oil temp holding on 210,oil pressure is 25 psi,light never comes on.....with my motor the 250 rpm idle increase is good for 5 to 8 psi of oil pressure,I have left the idle on 900,would rather have a little more oil pressure than lose a motor,the extra gas it burns is cheap compared to an engine rebuild..........
David