Small Block Chevys seem to run okay as long as they have 40 psi at hot idle. I had a machinist make a mistake on a crank once, and the hot idle was only 25. It went downhill little by little, and by the end of the month only had 10 psi at hot idle. I gave the machinist Hell over that and also gave him some not-so-good PR
. Some speed shops took my word for it and took their business elsewhere after that.
Small Block Mopars like higher oil pressure, such as 60-80 psi at hot idle. It is because of the way the oil passages route inside the block. There is a fix that involves putting an oil bypass line in the valley, but I don't like doing that. If anything breaks, you can't see it until the engine goes south on you. I still remember the external copper top end oil line on the old "Y" block Fords that would work harden and break. Oil went everywhere. What a Mickey-Mouse outfit that was. "Have you driven a Ford lately?" lol