When I sent my pump in to be rebuild I was told that it was set at 160 psi of rail pressure. I got it rebuilt and the shop set it at 200 psi. Now it's up to around 290 at
WOT before free rev. No idea what mileage is like.
My 855 is the first big diesel I've owned. I've always been a
Cat guy and known about Cats because that's all my father has owned. I really like this motor, too. I am really looking forward to messing with it more and trying to make the power I've been told by many that I can't make, with a small cam.
FLD, just remember that there's motors may be rated at 400 hp from the factory, but that is flywheel horsepower. You should figure about 25% driveline loss in power. So, 500 hp at the wheels is a lot different than 500 hp at the flywheel.