I can't offer you any advice concerning the metal flake source, but I will offer this regarding the oil pressure:
1. What type of oil filter are you using? I tried the Fram Extra Duty once on my 91' GTA and it very quickly developed the same symptoms you describe. Started using regular Fram and never had a problem again. You may want to try a Napa or Carquest Filter (they are made by Wix). I use the filter listed for my 94' Suburban on all my SBC engines. This is the longer style filter (i.e. Fram PH5).
2. Try running a conventional (or blend) 10W40 or 20W50 and substitute one quart of Lucas Oil Stabilizer
for one quart of oil. I have found with my engines this will take the oil pressure from say 15-20 lbs. at idle (hot) to about 25 lbs. And, I have read articles that compare synthetic oil to conventional oil where synthetic holds slightly less pressure then a conventional of the same weight.
3. What type of oil pump are you running? I learned that a Moroso "Racing" pump that has the "anti-cavitation" slot in it will hold less idle pressure. This is from personal experience and later confirmed by Moroso that low pressure is inherent with that style oil pump. These pumps will hold about 10 lbs. less idle pressure than a normal or high volume Melling pump.
Seems like if this is your first oil change and it is a flat tappet cam, you are probably okay.
Good luck solving this problem; and I hope it is nothing serious, Ed. www.edgesz28.com
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