Supercharger lubrication

I'd say yes, you'll have problems because you will basically pressurize your compressor bearings housing, will fill it completely with oil, and then the pressure would have to force the oil back to the sump. It''s more likely to see many problems with oil seals with this configuration. In commercial applications, if you have a small heigh difference between the oil return point and the sump, scavenge pumps are used.

If the compressor position is mandatory, I'd think about installing a oil sump and scavenge pump for the compressor. But it's becoming complicated, more components to give you problems in the race, and to spend energy that could be directed to the wheels.

So, If I were you, I'd choose to increase the turbine and/or compressor tubes and hoses to a convenient position, instead of making this arrangement.

In dry sump engines they use a small pickup pump to pump the oil into a reservoir. They are simple to hook up.

In a vessel or dry sump, undoubtely works well.

But it is still another pump to deal!

Most dry sump pumps have 3 stages, 2 scavenge and 1 main. It's easy enough to add another stage and use that, and they are very reliable. I've only known one to fail due to crash damage.

If you don't find a way to get the extra oil out of the compressor, you will drown your bearings in oil. You don't want your bearings to run in a bath, they work better with a light coating, as I'm sure your instructors have taught you. First you have to overcome the forces of the oil bath, loss of efficiency, then you get what is known as oil whip, that is a condition of too much oil coming between a shaft and a bearing, that can be seen as vibration in the compressor that should be about 1.5 to 2X rotation.

Good luck

I doubt if you will have any problem. Turbo bearing inlet oil pressure is what 40-60 psi at least. Turbo bearing outlet oil pressure will be some value less than that. What is the pressure in the crankcase much less than that right? Because the crankcase is vented to the atmosphere right? A few inches of height difference uphill from the Turbo bearing oil outlet to the crankcase sump will be insignificant.

The answer to this question is very dependant on the type of supercharger you are planning to use. Is it a positive displacement or centrifugal type? If it is positive displacement you will have two meshing gears contained within the bearing housing which must be run in an oil bath and not completely submerged. If it is a positive displacement type I would suggest a self contained sump for the supercharger. If it is a centrifugal type the main concern is maintaining a healthy flow of oil through the bearings. Provided the superchargers required inlet oil pressure + the backflow oil pressure provided by the head pressure of the sump = the available pressure at the inlet of the supercharger from your oil pump I would feel very confident about the set-up. Also by having the supercharger mounted below the sump you will be guaranteed that the supercharger will be full oil oil when you fire her up.