Dry sump

I have been running a dry sump setup for years and while I am by no means an expert I will share my thoughts. The number of stages affect two things. The amount of air/oil being pulled from the crankcase and the number of places it is being pulled from. Getting the oil back to the tank is important therefore more stages placing pickups in multiple places is a good thing. Depending on how loose the engine is more stages will also work to pull a vacuum in the crankcase aiding in oil flow and ring seat allowing low tension rings which in turn lowers friction losses. The drawback of more stages is that it takes more power to turn the pump, creates more aeration of the oil and more heat. I would recommend at least 3 scavenge stages. That way you can place three pickups in the pan to ensure good scavenging under different g forces. A fourth section could be used to pull oil from the lifter valley. You should also look into a vacuum regulator to ensure that you do not pull so much vacuum that you start damaging engine seals. If I remember correctly 13 inches of vacuum is where benefits really start to show but do some research to confirm.

Helpful answer thanks Blaine,

I am building a clean slate engine doing something I have not ventured into like this before. Using other samples I saw some race engines set up with 5 stages and it seemed a little unnecessary to have 5; but then again maybe I don't know better. I was figuring on maybe 4 if I can tap into the lifter valley.

Remember that the number of stages inlcude the pressure section ie. 5 stage pump has 4 scavenge sections. I had a 5 stage on my motor. Three stages pulled from the pan (front, center, rear) and one pulled from the lifter valley.

Do you ever use drain back ports in the valve covers for pick up points?

I have never personally used them. I would expect that with that with the scavenging in the crankcase and breathers on the valve covers it would serve to pull the oil out of the rocker area anyway.

quote:

Originally posted by PanteraTurbo:
I have never personally used them. I would expect that with that with the scavenging in the crankcase and breathers on the valve covers it would serve to pull the oil out of the rocker area anyway.

Since some of the residual oil that collects in the heads/valve covers is used to cool the valve springs/valve train.

I would be concerned about scavenging this oil too quickly.