stiknruda
My first suspicion would be that either the prv has been adjusted to improve pressure or something is preventing the ball from becoming unseated.
For me it looks like the release valve is working as it should, that's the reason why the pressure stays at 90 psi for every rpm.
If the passage of oil is partially blocked, the pump is pressing the oil through smaller throughput causing higher pressure. This forces the oil through the release valve.
My concern is that part of the engine could not be lubricated...
Is there a way how to look after this?