SwayBar

Aw man, puh-lease noooo......

BC

Mark A had some issues with a different dry sump pan. I wonder what they were? The only other stuff I know about drysump is that it must have scavenger pumps to put the oil back in the tank, and the oil pump on our car could be used to draw from the oil tank. Seem simply enough?

slate blue

Interesting guys, so from what has been disclosed nobody is actually pulling a vacuum because from what I know a 2 stage pump probably can't pull a vacuum and if you overun the pump that will just lead to increased wear and tear on the pump, so that is fair enough.

However unless you pull a vacuum you will not get a power advantage, any windage reduction will get taken by running your pump. The other thing is the quality of the oil supplied back to the engine. The guys with the large tanks in the back of the car will IMO have high quality oil as the air will have plenty of time to sort itself out.

I was going to run the tank there but I have some problems with doing that on my car that will see most use on the street. So putting where Ferrari puts theirs on the 599 seems to be the go. That is in the front guard. The other thing is given I will have a high revving engine, it needs a very high quality supply of oil.

With the Verdi you get something unique, you get an oil air separator. Pictured here, it also makes the plumbing easier on a multi stage pump.

http://cgi.ebay.com/ebaymotors/AUTO-...#ht_500wt_1182

It fits on the end of the pump and starts getting the air out before the oil leaves the pump. These pumps while obviously bigger than a 2 stage pump shouldn't be too much heavier as they can be optioned with lightweight parts. They will pull a high vacuum and make free power, free that is after you pay for the pump. It could be quite a few HP too as Auto Verdi claim 3 to 6 over other pumps like mine, notice the spur gears, not rotors.



http://www.autoverdi.com/pumps.html

The breathers need to be preset to the level of vacuum you are requiring, sounds like john's are in a good spot, I am thinking to use the S4 radiator air filter for this purpose somehow. It would be good to make use of it.

I think having extra pick ups is just taking the development to the next level, the extra vacuum along with more pickups and I am thinking that with 5 stages you will be able to stop the heads draining backing into the sump. It gets extra power for free which is the way modern engines are going in, i.e extra efficiency.

Greg

P.S

The reason I have been thinking about this is that my 2V project may go in the wife's auto now and given I will not be buying another 928, or a third 928 (as we have a new baby) basically I have all the parts, would swap out the Ti intakes as the autos don't rev and don't need that. The 4V work I have done would be lost, which would be a shame. So I may do that for my car.

ptuomov

Doesn't the vacuum that a pump pulls mainly depend on the amount of blowby and venting? What pulls a vacuum inside a well-sealing engine might be something much less than what pulls a vacuum inside of a loose old ***** of an engine with busted oil rings. I am venturing an amateur guess that just counting the "stages" doesn't tell you **** without knowing the engine and the pump. But what do I know. I know GG you get this, I am not bustin' your *****, just expressing mild frustration that nobody steps up to make a dry sump system for 928, presumably because of the expectation that not enough people are going to buy it. Either because they don't have the money (ok reason) or some other reason.

Since nobody makes a viable commercial dry sump product for 928, I'll from now on call the imaginary, nonexistent 928 bolt-on dry sump system the "dry hump" system.

A novice opinion is that one wants to combine a dry hump with crank scraper or two, all designed to play ball together. Whether or not the dry hump pump is attempting to pull a vacuum or not.

I don't know how practical the idea is, but your initial post (or one of the early ones) mentioned the possibility of placing the main oil reservoir inside the wet sump pan. Then combine that with a smaller high-up reservoir with the filler cap. If you can work that out, it's an excellent idea: Sealing the deep part of the sump (or hump) off from anything above it other than the usual pickup. Then scavenging above that deep part and feeding it to a small, tall tank pretty high. Finally, gravity feeding it down to the deep part of the sump. The dry hump pump only doing scavenging and air-oil separation duty.

The Lindsey 944 dry sump system that I lined to above has an air-oil separator, so it wouldn't be too shocking to expect the 928 dry hump system to have something similar. Is their pump Verdi?

???

I am all for efficiency but I'd like to see the 928 dry hump system turn into an actual dry sump system kit at some point. Even if it's as "basic" as the 944 system I linked to. That system has one decisive advantage over all the available 928 dry hump kits: It actually exists.

I just wired 800 American pesos to Australia yesterday for a set of test equipment. That's one fifth of the imaginary price of the imaginary 928 dry hump system. There's more of the US Treasury toilet paper for anyone in the world who comes up with a dry sump, instead of just a dry hump, system for the 928.

C'mon guys, you can make the world a 928 bolt-on dry hump/sump system down there! We helped you in the WW2, you help us now! (Actually I'm Finnish so we were on different sides, but let's not stick to irrelevant details.)

Hilton

By "S4 radiator ail filter" I think he means the small air filter location for the air-pump system.

svp928

Here is a link to very good system- these pumps are very efficient, and his air/oil separator is as good as a Cosworth. The billet pans with integral pickups and pump mount are really nice. Reasonably priced, as well...
www.daileyengineering.com/

IcemanG17

Oh boy here we go again........

Since I drove over 100 miles on track today...I will mention what I noticed...

On the lemons racer (wet sump) with an OB pan-pickup and a 3/8th spacer running Amsoil....I noticed the WORST pressure drops I have noticed ever in this track 928.....THEN I checked the oil.....and it was at 1 qt down....indicated..which is NOT 1 qt down due to the spacer..

So I fill it up to the "full" mark.....GUESS WHAT...the next session I was averaging faster laps and the pressure drops that had me concerned at 1 qt down were 25 psi HIGHER at full (over considering spacer).....

Again I'm not an engineer...only a guy that races a $256 928...

Just to clarify my "concerns" were 50psi at 4,000rpm with the low oil level....with a full level it was 75psi under the same conditions (with faster lap times)

Lizard928

Greg Gray,

I have built my own dry sump system for my car. I have not tested it though.

However I went with the dailey engineering pump that SVP links to. Mine does have the air oil separator on the back end of it. The pump weights bugger all. BUT you do need to keep in mind that pump is not cheap.
That pump cost me just over $2k. And it has been sitting waiting to go on for almost 3 years now......

I modified a stock oil pan similar to what Pace did. Alex doesnt seem to have a problem with his. So I am in high hopes that mine will work too. However I designed my system so that the pump can pump a ton more than the stock pump can. Basically I made is so that I should be able to pull up to 20 in HG vacuum in the sump should I so choose. However I had not planned on running that high without rifle drilling the rod to get high pressure oil to the wrist pin, and a piston squirter.

I will say that the pump is a work of art though!

slate blue

By Xlot
yes Hilton is correct, when you have a breather you need to filter that air or you are just sucking in the atmosphere with all its contaminants. You need to have the breathers set at a level that works with your pumps ability to pull a vacuum. So by that I mean, if you pump can pull 6" of vacuum you may have your breathers set at 5". Now that is only an example don't use the numbers literally. I don't have the numbers to post.

You need a certain amount of air to be drawn through the engine to scavenge it properly. Just think of a glass coke bottle and try and suck out the milk with your lips covering the neck. You can't do it but drill a hole in the bottom of the bottle and you will be fine. Same principle.


By ptuomov

So if you have this loose worn motor I would have thought that the vacuum pump would pull out the blow by first before triggering the breathers as such if the system was setup properly no dramas, they talk about this on Speedtalk. They said much better to buy a big pump that you can change the ratios on and keep up with wear as it happens.

I doubt it will be a Verdi, the Auto Verdi is the Rolex of pumps and not even all the Nascar teams use them, I suspect due to cost, just like the Laminova coolers and the Lysholm screww superchargers, they have world leading efficiency and the others copied them.
Well I think the implementation of that idea is where the difficulty comes in, what I did try to do was by the carbon oil tank off DCs and MWs Red Bull but they had been sold, they sell for peanuts btw, I haven't come into money. It would be interesting to see how the baffling was done as those tanks are going to be basically the same shape as the one needed for the 928 in the guard.

By svp928

Agree, there stuff looks like the Harrop engineering products made for the Supercars here, it looks the goods I have to say and they too have adopted the rotor style pumps. If you remember Tom Cloutier made a very nice looking CNCnd pan, I don't think we heard more about it which is a pity. Any one have any info on that?

Greg

stuartph

Greg


So if i have cam cover breathers this will be enough to draw some air back into the engine.

I plan on placing a 10L pace tank in the battery box once its been adjusted

John Speake

The Stroker racer in my Avatar ran with a Pace system all last season with no problems.

slate blue

Stuart, Pace are the engineers I am not, I am really just providing good quality info to the board and asking questions also. So when I deal with Professionals, such as Pace I just ask respectful questions. If you are comfortable with their answers go with it. I have found some things that seem straight forward are not and that is where experience pays.

Greg

g.orruņo

i found this:

http://www.gantspeed.co.uk/showroom.php?ID=26

slate blue

Yes that link was posted a page earlier.

Greg

g.orruņo

aa!! sorry!!