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The TT pump is appreciable in size and spinning at 6K produces about 70-80psi in the galley. If the oil pump wasn't keeping up you would see the pressure fall but I've only seen it rise as RPM increases. If there is pressure in the system, there's flow. If it continues to increase as RPM increases then I'd have to say its not falling short. SImilarly, the NA fuel pump can't keep up with anything over about 16psi. I had one in my car for some time and what I saw was the fuel rail pressure would come up as boost increased but at about 5500RPM the pressure would fall off as the demand for fuel increased. In the lubrication system of our engines, the variation of oil demand is the same in any engine RPM as the gaps in which the oil is being squeezed into are not changing. Centrifugal forces on the crankshaft will promote better oil flow to the rod bearings as RPM increases, but again, the static demand is based on the area of 'bleed'. In the lubrication system there is a little variation, but nothing like a fuel delivery system. This works to our advantage mainly because it makes it easier to comprehend the oiling system. Since the pump is mechanical and driven by the crank, the flow of oil is directly related to the pressure generated. Since the 'bleed' stays the same, as the engine spins up it will generate more pressure and also more flow. If the pump itself is good and the system makes typical pressure, it will never 'fall behind' since the pump is directly driven by the engine speed. Which brings us back to the rod bearing itself being the root of the problem. It wouldn't matter if you shove 1000psi of oil into that journal, it wont make it last any longer than if it is getting 10psi per 1000RPM. The oil pressure itself does not form the cushion for the journal - the oil 'film' is the bearing surface. The pressure just tells you if the pump is working and if the orifices are properly sized. If a rod bearing goes, the orifice size just increased and you will see a drop in oil pressure. Now whether you will see that on a stock guage or not I can't say. But an accurate oil pressure guage will tell you if something isn't right. Then again, a thunk thunk thunk from the engine tells all. I really dont think it is an oil pump issue else we should see the oil pressure fall off, but for the reasons mentioned, that couldn't be the case.
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