Dry sump tank size? any dry sump gurus?
 

I've never ran dry sump before and am trying to educate myself as much as possible before I start spending $$ on parts or just taking any vendors word as the gospel.

I've been doing some reading and too much thinking about my dry sump set up, where to mount the tank, what size lines, and what size tank.

Does anyone have any insight on sizing of the tank other than space considerations? Why choose a 5.5 gal tank over a 4.5 gal tank? It seems if you have the space a larger tank would be better to help evacuate the air in the oil and keep the temps cool.

Is there any reason not to run a 4.5 gal tank with a lower oil level to reduce oil puke vs say a 3 gal tank with the oil level closer to max?

The majority of the tank capacity at most times could be escaping air so it seems more tank capacity would be a good thing. As long as the oil level is above the baffle and the pickup completely immersed in oil your good right? :willy: :willy: :willy: :faint:

If you had hundreds of thousands to spend like OEM, you could figure out what keeps the engine happy temp wise on the street and track. You don't have that luxury so I'd over engineer and deal with the consequences.

2 gallon under hood... 3gal+ in the trunk.

I'm with you on that. I'm just not sure what is over engineered vs just enough at this point.:rolleyes:

I'll be bugging Dailey on Mon since I'm going with his pump and pan and do some more reading. Aviad usually packages a 3 gal tank with their systems. I see a lot of NASCAR tanks for sale that are 4.5 gal. I figured someone here has some track miles with a set up that would give me a baseline.

Interesting. Why would the tank in the trunk be bigger. I know the recommendation is to run a larger line to the trunk. :question:

added security IMO oil has a farther distance to move.

and the bling factor is upped 10 fold.

Matt

I had the same questions when I was researching this heavily recently.

I believe you are supposed to never run a tank at or near full capacity? Pretty sure I read that as the norm. Did you find info to the contrary?

I was told 2/3rds to 3/4 full... from lots of different places

No I had read to reduce the oil level if it was puking a lot out the breather. My thought is that with a bigger tank it would be less sensitive to this.

:thumbsup:

Makes sense to me.

"Nothing makes a pump anything more than a pump. The idea is that you will size up the amount of oil you plan on running through the engine and stage (both size and number) accordingly. Too little and oil stays in the engine too long and you have problems, too much and you bleed energy into pulling more vacuum than you need.

Now you can run gear, rotor, or a combination of both. Most of the pumps that people talk about are going to be of the latter variety (more expensive and better performing). The pressure stage will be a gear section while the scavenging stages will be of the rotor type. The rotors do a much better job of moving air and allows them to be 1) more efficient when they don't have oil to move and 2) able to create more vacuum and eliminate the need for a dedicated vacuum pump.

Even in the realm of rotor pumps there are two types; the first will have standard lobes that are cut straight. These are made up of the Dailey and AutoVerdi pumps (when purchased in cup form) and are run by a lot people on a lot of engines. The Frank Weiss Racing pump will have helicular cut rotors that are more expensive to produce and better at creating vacuum IMHO. The downside is that they do not pass debris as well as the other style so we don't see as many of them out and about (and when you do they often show wear). I have owned six stage versions of both Weiss and AutoVerdi (I have two six stage AutoVerdi pumps for my planned R07 build); both companies have excellent customer service with the edge going to Weiss (they go above and beyond in my experience). All in all, both are BA pumps!

As for how many stages; you can run what you want you just have to have a place to plumb it. Generally we run 4 pickups in the pan and one into the valley, but the only limiting factor is what you want to do. If you need to pull oil from somewhere you can stage for it, if not you can increase the size of a pan section and pull more from there. General rule of thumb is the more scavenging stages you run, the more it will pull out, meaning either increased oil flow or vacuum"

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"Well there are a few things to look at when you pick out your oil tank. The biggest thing is to make sure it's a good unit with all the trick baffles that will keep the pump fed with good oil (the foamy stuff should stay up at the top and sides). The two piece Peterson tanks are nice because you can set the baffles location and clean them up as well. Some will have a drain on the bottom and others will not so that's something to look at if you don't want to suck the oil out of the vent.


As for capacity most generally run as much as they can fit in the chassis but depending upon how you’re going to filter it dumping 4 gallons of race oil into the tank all the time can get expensive. In a drag application you are not fighting oil temps or overall usage like someone that's running for an extended period so you can get away with running less if you would like; fuel contamination will take the oil long before usage anyway. I don't foresee you running a lot of additional oiling so with a good pump you shouldn't have any problems getting the oil out; so having a massive amount of reserve capacity isn't as much of an issue when you are not running 16 piston oilers and 16 valve train oilers like the cup stuff.


For example a sprint car deal cannot fit a huge oil tank so they run around 9 quarts give or take (some more, it just depends upon the setup). They don't use a lot of oiling tricks so they don't stack too much oil up in the engine (it will amaze you though just how much is in there at any given time). Another thing to consider is that it does take a while to heat 5 gallons of oil up even with the nice heating probes that come in a lot of cup tanks. So if you are really spot on with your program and need to have the oil at a certain temp before start up you may find yourself waiting for the temp to come up.


All in all the tank comes down to how much oil you feel you need and if you can fit it in there; at one time you could find a lot of top notch cup tanks around for 30% of the new cost with heaters and such. If you can find one and it will fit that would be my weapon of choice"

^ Good info (it appears) but who is the author?

YB search ;)

http://www.yellowbullet.com/forum/sh...mp+tank+to+use

The Only think im worried about is oil temp's i think I will have to use a T-stat with a pair of probes.

i talked to peterson about a larger tank and not filling it as much. they said that this could cause the tank pickup to become uncovered at high rpm and high gs. their suggestion is to check oil level at a steady 3k rpm and fill it to just above the top of the baffles. this of course will be different depending on the rpm of the motor.

my plan is to run one of their 7" drag tanks. all the baffles are the same as the others. they claim its 1.5 gallons, but i get 1.8 to the baffles based on their drawing. i get about the same for the ats/peterson 6x19.5" tank. the nice thing about the drag tank is the attached catch/breather can. if mounting space isnt a huge issue, this appears to be the cleanest setup. plus, its only about 40 bucks more to add the breather. the other setup require 2 -12 fittings, line and a $100 tank.

you guys worry me with the "heating oil" comments. im thinking this is for race motors with certain bearing clearances and not a motor that was designed for some street use.

Where have you guys been this last year of DS R&D (googling and foruming) ;) This is the best reading about dry sump I've seen. All "smart/make tons of sense" arguments. I always thought the tank size was just a matter of room.

What about the gear percentage? All I have found is that I would be ok with 50%. I'm building a only scavenge system (2 stages external pump), stock pump for pressure, daily street driver / some weekends track car.

Should I try different percentages by changing gear on a steady position, rev it up and measure the oil levels? What do you suggest to come up with the appropriate percentage?