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The Small and Big block standard volume (stn vol.) hydraulic pumps are pretty much equal in cubic inch displacement per revolution (CIR)

Ether pump could be installed in a small block and the horse power requirement to oil the motor would be the same assuming equal efficiency.

When comparing the Big and Small block high volume (high vol.) versions of these two pumps the small block is the larger volume pump.

The Big Block high vol. pump falls smack in-between the small block stn and high vol. pumps.

The difference in horsepower required at 70 psi is negligible as compared to 50 psi, all else being equal.

Using the pump sizing formulas available to anyone in the “Fluid Data handbook” for engineers, and measuring the pumps in question, I calculated the following; assuming 100% efficiency:

Small block stn vol. 2.45 gpm at idle (400rpm) and 18.4 gpm at peak (3000rpm) Engine rpm is double pump rpm.

Small block high vol. 3.06 gpm at idle (400rpm) and 23.0 gpm at peak (3000rpm)

Big block stn vol. 2.41 gpm at idle (400rpm) and 18.0 gpm at peak (3000rpm)

Big block high vol. 2.765 gpm at idle (400rpm) and 20.7 gpm at peak (3000rpm)

Horsepower requirement for a Big block high vol. pump at 60 psi and 90% efficiency is 0.8 hp

A Small block high vol. hydraulic pump will pump out a 5 litre oil pan 4.6 times per minute at 6000 engine rpm.

Seams to me running a High vol. high pressure Big block pump in a small block is no big deal.

Has all the taboo talk about high vol. high pressure been misinformed speculative Voodoo?