For reference I have a cast iron 5.0 - 347 stroker. Idle is 800 rpm.
With 10-40
oil cold idle is 65 psi - prv is open and hot 45 psi.
I didn't like the high
oil pressure when cold so i switched to 10-30
oil. The distributor gear stories always leaves me a bit nervous.
With 10-30 oil, carries 60 cold idle and 40 hot. It still pegs 65 psi by 5000 rpm (not sure where it actually hits 65).
On a 90+ F day and running hard the water temp was about 205 (normally 190), and it idled at about 37 psi with 10-30 oil.