Jim's the man.
I researched the tech info, and with Jim's high level of R&D, I went with a std vol. pump and put the spring out of my old pump(hp) in my 383. Even with the non restricted 440-1s the pressure stays at 55-60 , and drops to 45ish hot,hot idled down (900?). This was with generic 15/40 diesel oil.

I also run a BIG pan and crank scraper, stock pickup, 7000+ rpm.