Dry-Sump Oil Systems

Hey there, just was setting up some more things on the new funny car and was wondering if anyone could give some advice. We sort of logic-ed (yes I know that probably isn't a word) our way through the way the pump and lines should go, but just to make sure I drew up a diagram of what we thought.



Does this look right? Oh, and just so I know, the pump came with a stainless u-shaped tube already on the pump connecting two of the fittings (shown on my diagram)...what is this for?

Thanks.

 

The Plueger pump I am familiar with has separate sides for scavanging, and pressure.The scavenging path is pan to pump to tank. The pressure side path is from the tank to the pump, to the filter, to the block.
The port for "clean to the engine" is on the left or front side of the pump. This port is easily identified as it simply routes the oil 90 degrees and out of the pump into the block This port is plumbed to the outlet of the filter. The other fitting on the front of the pump is the pressure side discharge it is plumbed to the filter inlet. The rear fitting with the "U tube" is the supply from from the tank to the suction side of the pump.This line obviously must not be able to collapse reducing the supply of oil. The pan to pump connection is as you have sketched.
I summary the scavenging section discharges directly to the tank. The pressure section discharges to the filter inlet. Note the passage in the pump which routes the filtered oil into the block has a critical O ring at the mating surface with the block.(easily dropped/ misplaced). Also an o-ring is required on the drive collar which plugs into the block. The fasteners to the block torque to 25 ft#

 

One notable problem with your schematic is that the oil from the pan and/or dry sump tank can be aireated. A System One filter placed in the pressure stage section of the pump where you have the stainless hardline loop actually acts to remove a lot of the aireation before it re-enters the engine under pressure (that loop area is the pressure side of the pump which directly feeds the engine). Aireated oil spells disaster to the bearings.

Someone sells a small kit that removes the filter from the pressure stage side of the pump with a bolt-on item. The idea is to replumb the system like your diagram with the filter between the scavange side of the pump and dry sump tank. This is so the oil pumped out of the pan will be filtered of any metal contamination (blow up debris, broken lifter parts, etc.), before it reaches the dry sump tank. Great idea, sort of.

I've had discussions with Steve Plueger on this. Not all, but some who've done it the way your schematic suggests have had problems relating to lack of lubrication. Certain racers chased their tails trying to find out what their problem was, only to discover that what I'm saying is true. Steve has done or seen some testing which confirms this.

Good luck.

 

we run our dry sump like your drawing,gained 20 more pounds of pressure. but i made a plate like the opposite side of a oberg oilfilter and welded it to the top of the tank,put studs in it and bolted the opposite of the oberg set up right on it. with a real coarse screen,removes any airation from scavenged oil before it gets in the tank. our crank center line is so low our oil pans like a cover.(make sure you use AN line or flare tubing,no hose clamps) filtering the return side does back up some pressure.

 

Thanks for your input everyone. It all helps out. We have run a dry sump in the past on one of our dragsters, but just couldn't remember how it went together.