223 | Dry Sump Systems - Maximum pressure

Hi,

How should I decide what maximum oil pressure ideal for a specific application with dry sump?

Specially for a N/A engine converted to a high boosted and high RPM with loose bearing clearance.

Experience would be a good guide. I've seen oil filters fail at 120 psi, but I like to keep it below 100 psi when cold. Some ECUs have a provision to limit the RPM while the oil temperature is cold.

The usual rule of thumb is 10 psi per 1000RPM. So a redline of 8000RPM would 'need' a peak pressure of 80psi.

Go a bit higher for looser bearing clearances and/or very thin oil.

Personally I never bothered going higher than 75psi on my 10,000RPM loose clearanced 4age. The bearings would last a couple of seasons easy.

Just to stress the cold situation David mentioned. Dry sump pumps often don't have very good pressure relief valves (they are easily overwhelmed) which can result in VERY high cold oil pressure values...I didn't manage to split an oil filter but I did frequently blow out the front seal on the oil pump.

Thanks guys