Dry Sump

[Shad Laws]

Hello-

I'm going to elaborate a bit in an effort to clear up some confusion...

Let's ignore the oil cooler for a sec because there are many different variations on how to do it.

A typical wet sump system works like this:

Sump -> Pump -> Filter -> Pressure Relief -> Engine Oil Galleries -> Sump

The sump is basically a "catch" below all the engine components, using gravity to get the oil back in the sump.

A typical dry sump system works like this:

Oil Tank -> Pump Pressure Stage -> Filter -> Pressure Relief -> Engine Oil Galleries -> "Sump" -> Pump Scavenge Stage -> Oil Tank

The oil is drawn from an external oil tank (where aeration is removed and there are no moving parts to create windage) and put through the engine as normal. Then, one or more scavenge stages suck the sump of the engine dry, often taking up air, too. Additional stages could suck from rocker boxes or turbos.

Usually, the oil coolers for a dry sump system are placed on the scavenge side of the system - after the pump scavenge stage and before the oil tank. This means that they have no pressure running through them. It also means that the pressure stage of the pump takes oil as directly as possible straight from the oil tank to the engine.

Take care,