I made an oil pump test fixture to adjust the oil pressure and just play around.More or less submerge the pump pick up in a pail of oil,screwed a pipe into the outlet with a variable orifice bleed and a pressure gauge.A 1/2 inch heavy duty variable speed drill motor rated at 3000 rpm maximum drove the pump.A 235-261 pump lost 75 percent pressure at all speeds pressure with a 3/16 bleed inch opening.I set the pressure at 50-55 psi.
This same pump was used in my 261 build with .002 on the rods and .0025 on the mains,oil to the head was restricted by a .062 Holley carb jet pressed into the rocker oil feed tube.The engine has a full flow oil filter,the gauge hooked up to the outlet of the filter.
After a one hour ride at hiway speeds with 20/50 oil,this engine has 25 psi at 700 rpm and rises to 40 psi at 1200 rpm with 45 psi maximum at higher speeds
A real world test....
