Originally Posted by KULTULZ
Did you use a HV pump (MELLINGS hopefully) and did it come with two springs? You might want try the higher pressure relief spring and see what happens. Did you take a mechanical oil pressure reading at both the front and rear galleys?
Spring limits the maximum pressure, not the minimum.
If it did 45 cold then the spring will allow at least 45 hot === if there is any pressure available through the bearings.