Originally Posted By: billt460
Originally Posted By: eljefino
It's a "known fact" among prius drivers that running 1/2 quart low (from the top pip of the stick) has MPG gains.
And draining half of your blood supply can make you lose weight.
Part of the role of a sump, in addition to being a recepticle of oil, holding sufficient to supply the engine is to:
* give enough residence time for bubbles to separate out (hydrodynamics and air bubble don't work together)
* give enough surface area that the bubbles have the smallest path to the top
* keep surfaces away from the spinning assembly so that drops/streams don't hit a floor and either splash oil up, or break up and return as a mist.
* hopefully shed oil from the spinning assembly in the most efficent manner.
* do all of the above during any and all operating angles of the engine (including unertial effects from acceleration)
Air in the oil doesn't lubricate and pushes you quickly into boundary lubrication...the pressure and power loss is likely demonstrative of that...
If it sucked the sump dry, engine is toast on a dyno, although some drag racers will do that through the traps for that last poofteenth of shaft power for a second before shut-off.
If the crank runs into the oil, then it's really bad bad news, and poor design...LOL, saw an idiot when I was in the service stations put 3 gals in a 2.6 mitsubishi and drive off...sounded horrid, smoked badly.
In order to do what the video shows, the sump is grossly overfilled.
Regarding sumps, oil control, and G forces, I LOVE this video