Might be time to air test it to check for leaks.

You have base oil pressure straight away? Needle on the dash pops up quickly during cranking?

Very possible it's the original HPOP with a failing shaft seal or something else in the pump, if so like Randy mentioned spend the extra scratch for the good one. Countless threads of guys using the Ford remans, bad out of the box.....one guy IIRC had two bad in a row. Use the Ford o-rings however for the new HPOP.

 

It takes as long as 6 seconds for the gauge on the dash to move from a cold start. Setting for 3 hours, it took 3-4 seconds. 30 minutes to an hour takes about 1-2 seconds. On a hunch, I pulled the oil filter this morning, and it looks to me like it had drained out overnight (the filter wasn't dripping oil and the walls of the housing were pretty clean with very little residual oil). It is a Racor filter, and this didn't start right after my last oil change, it's been in there about 3000 miles. Would a bad drain valve cause this, and does anybody have the PN?

 

It would if the valves not being held closed or if the cap is the tall one... post a picture of the cap. A tall cap and stock filter would do it for sure!

 

It's definitely the OEM cap. Never had anything but Motorcraft or Racor filters either.