Another Oil pump issue

[87REDWAG]

Replaced my 360 w/ a used engine( 50k used???? if that can be trusted). Anyway other that the obvious, what would cause the oil pressure to not reach full potential, and drop the faster the idle/rpms are?

Cold start on mechanical gauge 50psi
Hot idle is 5psi
if I bring the rpms up to 2000rpms it will raise to 25psi then start to fall off the faster the rpms are. The engine does not sound like it is starving for oil....have had that before.

This is what I did to the used engine. New timing chain, oil pump kit seals etc. Did not replace the timing cover. I have since trying to figure this out installed a midplate for the pump. Not sure where to go from here. I would consider cam bearings or something internal if the oil pressure did not drop off...I would understand just plain low pressure for that. Any help is greatly appreciated.

[youdidwhat]

Replaced my 360 w/ a used engine( 50k used???? if that can be trusted). Anyway other that the obvious, what would cause the oil pressure to not reach full potential, and drop the faster the idle/rpms are?

Cold start on mechanical gauge 50psi
Hot idle is 5psi
if I bring the rpms up to 2000rpms it will raise to 25psi then start to fall off the faster the rpms are. The engine does not sound like it is starving for oil....have had that before.

This is what I did to the used engine. New timing chain, oil pump kit seals etc. Did not replace the timing cover. I have since trying to figure this out installed a midplate for the pump. Not sure where to go from here. I would consider cam bearings or something internal if the oil pressure did not drop off...I would understand just plain low pressure for that. Any help is greatly appreciated.

different oil pump but that is just what my pump did when I got a ton of muddy water in the engine, it seems liquid sandpaper does a number on an oil pump. I'm talking about a DC pump not AMC so it could be another issue alltogeather