[SuperHatch]

Originally Posted by Olympiadis

From the factory, the sump and oil level are designed to supply uninterrupted oil flow through the engine for extended periods at wide-open-throttle up to red-line or limiter imposed rev limit of the engine.
I have no idea what temperature range this is good down to.

I don't think anyone can give you an exact answer for two reasons.

First "to achieve full lubrication" - but under what conditions?
hypermiling? dirt-track racing?

Second, sump efficiency differs with design, and drain-back characteristics can be affected by many variables such as sludge build-up, core-shift in block or head, or the alignment of holes in the head gasket. Bearing leakage changes as clearances change, and that will obviously affect oiling requirements, pressure, and drain-back.

This is somewhat unrelated, but I know of a few drag racers who have got away with making WOT passes while 1.5 quarts low (3-quarts remaining) without experiencing pressure loss or problem. From this they saw a performance increase of between 10 and 15 HP based on their trap speeds at the end. I do know that they were using standard un-baffled pans, but one of them used a windage screen.

I do know that oil volume requirement is at least in part a function of engine speed, and thus low RPM cruising (hypermiling) would have less demand than what the system is designed to cover.

Identical post times with near identical answers