Oil Pumps - a multitude of styles
Pretty much what Mattax said.
Once an engine is fully warmed up, a standard pump is not going to put out much more than maybe 65lbs.
Stock clearances and 6000 rpm=stock pump.
Add loose clearance to that and you should still be good at under 6500rpm
Add 7000 rpm to that and now you should run a high pressure spring.
Add full groove bearings to the above and now its time to fit a high volume pump with the high pressure spring.
Most people are fine with a std pump.
But ultimately the bearing clearance and rpm usage are the deciding factors.