This is all very entertaining, but kind of a waste of time except for watching some of you "duke it out". Since the originator didn't give enough information to do a proper analysis all we've been able to do so far is some wild a$$ guessing.

First, oil pressure in and of itself don't lubricate squat. It is meaningless without some points of reference. Oil lubricates bearings, not pressure. Oil in motion creates the hydrodynamic film. Hydrodynamic films exist all the time in non pressure fed systems. Just ask anyone with an old Chev, Hudson, etc with "splash" lubrication systems as well as countless industrial applications. Heck, wear some new leather shoes out on a slick, water covered concrete surface, you'll get an empirical lesson in hydrodynamics..................without benefit of a pump. If you plugged the oil pump outlet three inches down stream and took a pressure reading on that section of line you'd get a pressure reading, but the oil wouldn't be getting to the bearings. Right now someone is saying that isn't plausible. Well, the three inches may be off, but it's been done by some installing a bypass valve backward or hooking up a remote oil filter incorrectly. Couldn't understand why the engine seized because they had pressure! Give me oil flow before oil pressure any day. The value of the pressure reading is only meaningful if it deviates from the norm with no other changes having been made, or changes in the environmental conditions.

So, while some of the guesses above may be correct, there are other possibilities. Does he have a crappy filter that is restricting oil flow at low rpm, and only registers a reading when the pump is pushing harder (dumping the bypass in the filter)at higher rpm's? Is he using too thick of an oil, different than what was in there when he last remembers seeing the pressure? Was the oil pressure reading similar to this before he diddled with the engine, but he didn't notice it until he became forcused on the gauge because of the work done? Are the ambient conditions the same (temp both ambient and engine, rpm, etc.) as when he saw the numbers he remembers? Does this 0 to 35 psi stay the same whether the engine is cold start or warmed? There's more, but until he starts to check off all the variables this just continues to be a guessing game.