I have enjoyed all the wisdom available on the variuos FE forumns. I have a cronic low oil pressure problem on a fresh 352 rebuild. Main and rod clearance is .001 to .0015. I'm running 10-40w and a melling HV pump. In the morning, about 60DEGF, I get 60 PSI at 1,000 RPM. Has the engine heats up, idle pressure drops to 5 PSI. Here are the readings at 185DEGF engine temp.
Idle 5 PSI, 1000RPM 10PSI, 1500 18PSI, 2000 28PSI, 2500 39PSI, 4000RPM 50PSI. All readings from a calibrated guage. Rocker shafts are remanufactured. At idle, the shafts are dripping oil but not "running" oil. At idle, I get an occasional oil light. The engine runs good and there is no valve train noise. Melling tech support advises they suspect engine clearance issues. The original brake-in went bad as a had a cam lobe go flat. On teardown, I found cam bearing #3 totally destroyed. I tore down the engine, cleaned it and installed new bearings, using the poper tools. The new cam turned freely. When the second cam broke in, I had 80PSI, at 3500RPM, at first. As the engine warmed up, pressure dropped.

I need to get back on to my twin turbo Mustang Fastback project so I'm thinking about using 20-50W and forgetting about this for a while. The truck is a ranch truck with occasional use. This FE has taken way to much time. I could have rebuilt three SBF fords in the time I spent on this truck engine. What a pain!

 

I see you put in a HV pump, that increased the amount you are pumping, but not raised the pressure. With only .001+ clearance it should have good pressure as is. The reason for no noise is probably the high volume of oil you are pushing. For instance a 1/2" hose at 30 psi gives X amount of oil, a 1" hose at 30 psi give 2X amount of oil(basically twice-not exactly but for this demonstration). I would not get too worried about it unless you cut open a filter and see metal particles from hard contact.

I have always shimmed the HV pump by .10 to increase the available pressure. I drill/tap the place for the plug and insert a pipe plug. I set it so it goes in .10 deeper than the original sheetmetal cap. Works great. It bumps the pressure up 20-30 psi at 6000 rpm. All my hotrods are set up this way with no problems. Idles at 35 hot and runs 80+ at WOT.

For a quick check try putting a holley jet in the oil galley in heads(under rocker pedestal) and see if it helps boost pressure. I install plugs in mine and drill them .06. It maintains enough oil for rockers but does not let too much blow by. You can pull the rockers, drop in a jet and bolt back on rockers. If you want then you can remove them with a small pick.

Just my .02
Larry