Oiling questions?

[V8KILLR]

Hey guys,
This may be a set of dumb questions, but gota learn some how. What is the difference between dry and wet sump oil setups? Please give me a focus towards S2 motors, as in which is better. Is it some thing that has to be custom made, if so, who makes them?

Thanks,
Jason

 

[NJTurbo]

Dry Sump is a oiling system external, like a Duttweiler pump sucks oil externally from the oil pan, the oil pump on a Dry Sump is mounted externally. Most of the S2 circle guys ran a dry sump as in a wet sump the engine would starve for oil as the cars went around corners, the oil would slush to one side.

Wet Sump is a oil system were the pump takes oil from the oil pan and the oil pump is mounted at the bottom of the block inside the oil pan.

Opinions vary between the 2, I like the dry sump set-ups. Some S2 blocks have provisions for a wet sump some do not. Depending on what you can find out there that is not junk, if you find a S2 without wet-sump provisions, your machine shop bill will be a little more costly. Duttweiler sells a dry sump system, runs about $450.00.

Hope this helps You.

 

[ijames]

Um, I've always been told that the difference is not where the oil pump is, but where the oil reservoir is. In a wet sump, the oil is stored in the bottom of the oil pan. The pump sucks it out from there (it doesn't matter if the pump is in the pan or external) and sends oil to the filter and bearings after which it drains back into the pan. In a dry sump there are scavenging pumps to suck all the oil out of the lifter gallery and pan and put it into an external tank. Then the pressure pump draws oil from that tank and sends it to the filter and bearings. Ideally there is only a thin film of oil in the bottom of the oil pan. This minimizes the oil picked up and slung around by the crankshaft, which saves several hp at 7000+ rpm (I've read claims of 10-15 hp), and the oil tank can be tall and skinny without dragging on the ground like a pan the same depth would, so the oil can effectively deaerate so the pressure pump always sucks nice oil and never foam. Usually the pressure and scavenge pumps are made into one long housing that is then driven by a single belt off of the crankshaft. The pumps and tanks are off the shelf items (about $1000 for a pump with one pressure stage and three scavenge stages if foggy memory serves), the plumbing and bracketry are custom. Going to Englishtown for the Labor Day GN-Mustang wars, I was struck maybe three or four years ago by how suddenly all the GN's that year had gone to dry sumps, when in previous years there would be maybe one dry sump and 6-8 wet sumps in the sub-9 second cars.

 

[KendallF]

Carl is correct. The Duttweiler setup could be properly referred to as an external pickup wet sump. Running a dry sump in a street car makes for some packaging problems, trying to fit the pump, the multiple lines, and the oil tank.

 

[V8KILLR]

Thanks guys for clearing that up, Dry Sump it is.

Jason

 

[Ron Tarabori]

Carls description is right on. One nice thing about the dry sump is that you can mount the tank anywhere. Most circle trackers mount it over the left rear to get more weight on that corner.

 

[EightSecV6]

A dry sump is a sealed system with no breathers and NO OIL LEAKS as it will maintain a vacuum in the crank case for better ring sealing and virtually no windage.Rule of thumb is about 40hp per pump stage on a large displacement engine such as a BBC. I use a 4 stage Moroso pro stock pump, and because my turbo is mounted so low, one stage is tied into the turbo return, works like a champ!

 

[V8KILLR]

Thanks Billy and all the other info given so far. I like the idea of it being sealed. No more blow by out the breathers.

Jason

 

[10SV6]

Originally posted by EightSecV6
.Rule of thumb is about 40hp per pump stage on a large displacement engine such as a BBC.

Bill, is that a parasitic loss of 40 hp or a gain from reduced windage and better ring seal ?