Yet again .. this topic appears !

Come of guys .. through a given and set passage size(in the block and heads) ..... there is no diff between a hi-pressure and HV pump.

HV pump is a waste of money, adds heat, and a power robber.

I've told this story before, but I will tell it again.

I reringed a 440 a while back(a year or so), and threw in fresh rod and crank bearings.
No crank machining or rod resizing was done. Clearances were .002 on the rods and mains when done.

When I started the motor, the pressure relief on the std vol pump stuck. This means that full volume of oil was pumped into the engine.

Keep in mind,
Oil Pressure in an engine is the result of forcing a volume of oil through the clearances. More oil = more pressure, and less clearance = more pressure. A high volume pump will restore pressure in worn engines, because it forces more oil through the clearances. A high pressure pump simply has a different pressure relief.

Back to my motor....
At low idle speed, the motor immediately blew the filter off, and destroyed the electric oil pressure sender.

So, in a motor with relatively loose clearances (compared to a freshly machined motor) a std volume oil pump moved enough oil to blow the filter and sender up at IDLE speed.

I will never put a hv pump on a fresh motor.

They are for restoring pressure in worn out engines, NOT for providing some sort of magically improved oiling in a freshly machined motor

My street 512 has fairly tight clearances in it but it does have full groove mains. With a HV pump on it I can get 60+ psi with just a speed wrench on the pump shaft. So that is turning the pump by hand with a speed wrench and I see over 60psi. I don't think I turn it more than about 100 rpm or so since I'm not strong enough to go much faster. That tells me right there that I don't need a HV pump on the motor!