Interesting thing happened 2 nights ago. I have a 2009 Chevy Colorado with a factory 300hp 5.3L V8 all aluminum LS motor in it (gasoline), runs out good, especially in a "mini" truck. An old 90's full size Dodge Ram Cummins 5.9L pulls up next to me, rusty rockers and all, and nudges a few times to race, so away we go. He does not win or beat me, but I was pushing the pedal through the floor with 5800rpm shifts and I could not get him to appear in my rear view mirror. Neck and neck. We did this 3 times, once from a roll, all same result, I let up at 70mph each time. He had 3 people wide in his cab, I was alone. I asked what he had done and he said just lift pump, larger injectors, stiffer valve springs, governor spring kit, 1/2 turbo upgrade (hybrid), and turned up pump. That thing ran amazing. Lots of black smoke from a dead dig, but it cleared up once the turbo came on. I'm still in amazement that an old diesel engine of nearly same displacement ran a heavier truck and 3 guys at the same pace as my 300hp LS, in a vehicle 1000lbs lighter. His sounded great, no smoke or haze at idle, said he has a hard time keeping the auto transmission reliable. I bet. I think maybe some here have played with 5.9L's and have similar experience, Patracy has, if not others?
Point here, I think I am now shopping for a used "P" pump, such as what those engines came with (Bosch P7100). They are far more capable than the "MW" pumps we have, from what I understand. Fits and works on 8.3L, have to do something about an oil line change, but sounds easy. Some 8.3L's came with them, in non-MV apps. I think the marine 8.3L rated over 400hp used a Denso injection pump.