Can anyone please explain the following:
When the engine (351W with a remote filter, Mobil 1 15W50) is cold,
oil pressure at 900 rpm is about 65 psi. Increasing rpm also, as I think would be expected, increases
oil pressure. This situation holds as the engine warms up, that is, increasing rpm increases
oil pressure. The situation changes once the oil is hot (100-105 C). Max pressure drops to about 45 psi, which I understand, but an increase in rpm causes a small drop in pressure, which I don't understand. Conversely, backing off the throttle results in a small increase in pressure. Why the reversal in response to throttle changes between cold and hot oil? Anyone? Thanks.