I just put a 250 in my truck. when i start the truck the oil light stays off when i push the enige to 1000 rpms or more the light comes on. after 10 mins or once the engine warms up the light stays off. Also when i rever the motor up over 1500 rpms i get this screeching sound. I noiced the harmoic blancer has a little wobble to it. I been told i might have spun a rod end bearing. I check the oil pump it's working nine. I'm wondering if the harmonic blancer wobble could play in to the noise at high Rpm and could cause the oil pressure problem. Can any one give me any advice. Thanks

Is this a used engine?
The damper will not change your oil pressure.
Install an actual oil pressure gauge so you can see what your oil pressure actually is.

MBHD

I have the same question that buzzin has. In my experiance, I never use a used motor without tearing it down and lapping the valves, ball honeing and rings and bearings. It sounds like you have a spun main bearing. If the donor car has been hit hard in the front or the motor was dropped, it is really easy to bend the crank snout. This would cause the wobble you mentioned.Just my 2 cents.