With all this good discussion on oil pumps and pressure, please
consider that insuffecient oil pan volume increases oil temps, increased
pressures increase oil temps because they are forced through and don't
spend enough time in the pan to cool. Also consider increased pressure
will "wash out" your weekest bearing faster and faster as it wears the
clearances like a dripping faucet will cut out brass seats at your
kitchen sink. It actually woks in reverse of viscosity where to thick an
oil does not provide sufficient lub to beatings and hence the metal to
metal contact wears the bearings. Its all relative! Finding a oil,
viscosity, capacity, relative to engine condition, environment, pump
pressures, pump volume, while controlling temps, your operating
enviromenent and no over or under lubricating and washing out bearings.