High volume and high pressure are not two different things. The pump creates
oil flow to the moving parts in the engine. The pressure you see is "whats left" of the
oil as it "leaks" past the moving parts. The issue is not really high volume vs. regular volume; its how wide are bearing clearances and what is the pressure relief valve set at. Find out from the engine builder what the internal clearances are, then buy a pump.
auto10x
Bill