Thanks for everyone's comments. FWIW, this is just a logic exercise. I have used 10W-30 throughout the life of this motor. I've had some significant problems chronicled on this site elsewhere. Hopefully I've finally found and cured all the gremlins that led to this state. Failed EFI attempt, bad 6AL, broken springs, bad valves and guides, broken pushrod guides, and finally a total heads rebuild - I'm ready for this car to have more than 50 miles per year.
I had read the article on
oil that I referenced and was just thinking out loud. Hopefully, as Brent noted, it was all a bad set of heads causing all my problems.
Oh, and I have a normal pressure, high volume pump.