Almost every single racing gear-type oil pump I’ve ever seen likely has inlet cavitation issues. They all seem to be designed with insufficient inlet port area, excessive flow velocities, and abrupt changes in flow areas that will produce cavitation.

Having an effective swirl pot de-aerator, or a mechanical centrifugal device like that used on Cosworth scavenge pump assemblies, is a definite must with oil systems that have a high turn-over rate.