The "Throw Away 318"

I think the stock LA oil pickup tube to the sump is 10 inches of smaller than 3/8" and the outlet of the pump is like 13/32", then the block to oil filter and back is also 13/32". Opening that all up to just 1/2 inch is free horsepower as the pump is not working as hard. Then opening the main bearing feed holes by 3/32" is even less restriction to a place that NEEDS more oil.

A High Volume pump using all stock restrictive ports is wasting about 15 horsepower.

Doing the Sanborn mods, adding the Kevco type pickup tube and a Stock volume pump will gain you maybe 5-10 horsepower over STOCK for a net gain of maybe 25 HP.