What is normal oil pressure for a 350 sb Chevy when hot?

Answer 1

That varies a lot from one engine to another, but if it doesn't have at least 15-20 lbs. at idle when hot, you might want to try a thicker oil. If that doesn't help it might be time for new bearings.

The oil temperature will affect how fast it can leak past bearings. When it's cold the oil will be thicker and harder to move past the bearings. But once the oil heats up it gets thin, more like water. The numbers on your oil can determine the oil thickness. Lower numbers mean that the oil is closer to water, higher numbers mean that the oil will be real slow to pour.

There is a "bypass" valve inside the engine that won't allow the oil pressure to exceed a specific setpoint. The valve is controlled by a spring and different engines will have slightly different "bypass" pressure because the springs are a little different.

Make note of where the oil pressure runs normally when the engine is cold. If everything else is OK the bypass should be preventing the oil pressure from going too high and when cold it should be consistently at the setpoint. If the oil pressure drops much more than halfway once the engine warms up, switch to a heavier grade oil (higher numbers). Like the previous poster indicated, if that doesn't send the oil pressure up, rebuild the engine.