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Discussion Starter #1
I use low tension rings and a vacuum pump on a NA motor. I have heard people say that a dry sump oil pump creates vacuum as well. So I'm considering switching to a dry sump system and wondering what the pro's and con's are, besides cost and "clutter".
 

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AKA Blownjet 468
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the only con's to a dry sump IMHO, is what you already posted!:)(and of course, having
to send all the new fittings, brackets, pullies, etc, back to have them annodized gold!)
:)devillove your setup, it's over the top!:)devil
 

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I agree with Blownjet.. I can't think of any cons other than cost, clutter and weight..

Pros: Less windage in the motor, Constant oil feed regardless of acceleration, deceleration, hard turning, etc.. Provides some more vacuum on the motor..
 

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I agree with Blownjet.. I can't think of any cons other than cost, clutter and weight..

Pros: Less windage in the motor, Constant oil feed regardless of acceleration, deceleration, hard turning, etc.. Provides some more vacuum on the motor..

X-2 on the constant oil feed . I have a Barnes pump , with all gears(on the pressure and scavenging side), on my blown motor it spit a valve cover plug (rubber push in ) into the lake . JMO if you wanted a lot of vacuum I would get a pump with rotors on the scavenging side . ... E :)hand
 

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Discussion Starter #6
the only con's to a dry sump IMHO, is what you already posted!:)(and of course, having
to send all the new fittings, brackets, pullies, etc, back to have them annodized gold!)
:)devillove your setup, it's over the top!:)devil
Thanks for the compliment. Making them purdy is easy. Making them work, thats another thing....
 

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BTW -- I was going after oil pressure all the time (when slowing down), Not vacuum, ...E
 

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Some of the other cons are cracking fittings and having the inside of the suction lines collapse. I have only seen a line collapse internally once, but it was on the line from the supply line therefore not allowing oil to the motor. I have seen fittings crack a handful of times. Other than that it is the way to go. If I saw it as that bad of an option than I would not be planning two dry sump motors myself.;)

Paul
 

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Okay, next question. How many stages do I need and where to scavage from? I am using a Dart aluminum race block, if that matters.
 

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Make sure you support the lines and dont let them flop around. That will lead to broken fittings and line abrasion. They will not pull as much vacum as a vacum pump ( the ones Ive played with) so I dont know how much your pulling now. Did you ring the motor with the intention of a vac pump???
Other than than whats allready been said, really no cons other than cost and room.
 

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Make sure you support the lines and dont let them flop around. That will lead to broken fittings and line abrasion. They will not pull as much vacum as a vacum pump ( the ones Ive played with) so I dont know how much your pulling now. Did you ring the motor with the intention of a vac pump???
Other than than whats allready been said, really no cons other than cost and room.
Yes, I used low tension rings, planning (and currently using) a vacuum pump. I am currently pulling 12Kg. I assume that if the dry sump pump helps pull vacuum that I will just reduce the amount of vacuum currently being pulled by the vacuum pump to bring my total vacuum back to 12Kg??

When you say support the hoses, do you mean attach them to something, like a bracket? Why would the fittings be any more prone to failure with an oil line than any other fuel, water, or other hose?
 

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Make sure you support the lines and dont let them flop around. That will lead to broken fittings and line abrasion. They will not pull as much vacum as a vacum pump ( the ones Ive played with) so I dont know how much your pulling now. Did you ring the motor with the intention of a vac pump???
Other than than whats allready been said, really no cons other than cost and room.
older systems (like 10 years ago) used a 4-vane vacuum pump, instead of the 3-vane that can be used with the wet sump, to get vacuum up there. the newer systems can draw just as much vacuum without using a seperate vacuum pump.

cost is a biggy, but if you're trying to extract every last pony, you kinda need it. along with other "pro's", warmup is cool in that you can warm the oil, remove the belt and use a drill to pump oil through the engine before startup. kinda like a lift pump.
 

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The most vac that we ever saw that I can remember is 10 inches. I know the ring packs today you can run 18 inches, thats why I asked. You cant run a vac pump(that I know of) and a dry sump at the same time. It will fight each other and the motor will lose.
As far as supporting the lines goes. When you get done craming 8 lines ( depending on how many stages you run) in a small area the fittings get crushed in thier. You be suprised ( depending on room you have) on how much you have to move the pump for the belt with the lines hooked up first. You can crack a 90* or 180* fitting. Also support the lines because they will move (like a saw) and cut whatever they touch and are alot heavier than a couple of -8 water lines. It can be a bundle of hose snakes in no time on a boat. Cars you can run the lines more freely, but still secure them. Boats have floors and stringers plus the fn oil pan in the way.:D
 

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If you want to hit big vac numbers using a dry sump you have to use a lobe type pump. The gear and gerotor types just can't get the numbers. They will make vac, but not like a vac pump can. The lobe type dry sumps can get pretty close to a vac pump.

LINK: Auto Verde Dry Sump
LINK: Barnes 9117 Pump

Ahsumtoy , I think this true also( lobe pump ), I dont thing you would gain very much weight, ( my dry sump pan is lighter , the pump is a lil heavier ( when you consider the old pump and driveshaft ) then you would not be using your current vac pump ( how much does that weigh ? , add a aluminum tank (mine is about 5 lbs ) and some #12 hose Well ? But then you don't need as much oil also , ( I run mine on 6 quart;s ) , .
I run direct off of the front dizzy drive ( no belt ) also run a pressure switch that at 30 lbs it shuts off the Mag if something goes wrong .
here's some pic's ,,,( And YES it is a hose nightmare ) :)devil ....E:)hand

 
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