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223 | Dry Sump Systems

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Hello Guys,

I have a 1500hp twin-turbo 2008 Lamborghini Gallardo Superleggera, running mainly 800hp daily and on e85, and I have a dry-sump system installed from the factory. But, with the TT, which is not a factory set up, it's not getting the oil pressure I would like to see when the car reaches oil temps (100 - 110 celsius) under a heavy load boost...

On Startup (cold), I see around 5 to 6 bar of pressure. When heading to the freeway, which is nearly the warming period it needs, I see a drop in bar as the oil warms up to a 3.5 to 4 bar reading which is around a cruising speed of 3000 RPM or so. This seems to be somewhat normal I think, but as I enter the freeway and increase the RPM's to nearly 8,000 I see a drop in my oil gauge from 4bar to 3bar and then as I shift gears it goes back up a tad again, so a DROP in pressure, not much but then back to 4bar and finally down to 3.5bar where it stays mostly.

As I cruise on the Freeway at 3,200 RPM's I see a drop in Bar to 3.5 or so. This is not good. I think I have an issue here with the Dry Sump flow... Something is definitely off.

I am running a Syvec remote ECU pack on my car, and I would like to see my charts if, in fact, I am dripping pressure or not???

I am running a remote oil filter with a -12 AN fitting to my engine, but the inlet line is not as close as I would like it to be going to the inlet on the motor. I am running around 3 feet of -12 oil line before it dumps into my engine...not sure if this matters or not.

I do have an oil tank that holds nearly 13 quarts of oil with a -4 vacuum line hooked up directly from the manifold to the oil tank. However, I do see a check valve that is located inline, more than likely for the boots I take it...

I also have a 2 line catch can running -14 lines. One (1) is coming from the oil tank can to the catch can (catch can is lower than the tank, FYI) and the other end is attached directly to the K&N Filter housing which is directly on the turbo air filer inlet airside.

OKAY - sorry, now that you know my setup, (sort of) my question is... "How do I make sure the dry-sump system is working properly, accurately, and efficiently? Why do I see a drop in oil pressure under boost and high RPMs??? Is this Ok?

Lastly, when I pull the dip-stick out to see the oil level while the car is running, I don't notice any vacuum pull on the system. I even took a piece of paper and placed it over the tube where you put the oil in and I see no "pull" in the paper, no sucking down on the paper at all. No vacuum.

Can you please help me figure this out? I have attached some pictures for you to review.

Thank you so much TEAM HP!

Attached Files

Does your Syvec's log oil pressure? You certainly need to have solid to data to identify if you have a problem, and then if you've fixed it. I would want to see Engine Speed, Oil Temperature, Oil Pressure. Nice to have would be crankcase pressure.

First solution with low oil pressure at higher temps is to use a higher viscosity oil. Generally the oil viscosity is chosen to provide the necessary oil pressure under the most severe conditions (hot, high-RPM).

I would suggest inspecting/observing the dry sump tank when the oil is hot (perhaps after a full pull on the dyno that showed the oil pressure problem) and and the engine is running (say 3000 RPM). Is the oil foaming? If so, then you may need to deal with that after the scavenge side of the pump and before it returns to the oil tank. I am thinking something like a Spintric:

https://www.spintric.com/new/

It sounds like you have some pretty sophisticated mechanical help if they could upgrade your engine to 1500 hp, I would be using their advise and experience to look into this issue.

Discussion points, more from a hydraulics' background.

Have you changed the hoses, and especially fittings - with the latter some designs have rather small internal passages and there are some large bore versions available which it's wise to use, anyway.

The oil pressure is pretty much independent of load/boost, being basically tied to rpm. So I would first check to see what the pressure does holding the rpm at various levels with the engine hot (or at similar temperatures). I would expect it to be similar - if it drops, stop, for this reason...

Dry sump scavenge pumps don't really pump oil, as such, but a mix of oil and air which carries the oil to the pump(s). Because of this there has to be sufficient air entering the engine to move the oil. It's exactly the same principle of a vacuum cleaner, where the airflow carried the dirt. If there's insufficient air entering the engine, it can cause scavenge issues - however, as you report the problem occurs under boost, where one would expect combustion gases leaking past the rings to also enter the sump, this 'may' not be the issue, but there may be a related one.

If there's a lot of blowby, this may result in increased aeration of (bubble of gas in) the oil, and if this is bad enough the air-oil separatoor in the dry sump tank may not be able to remove it all as the oil is continually being recirculated. There may be a noticeable drop in pressure because the pressure pump is a positive displacement type and rather than pumping the oil, some of the pressure (basically just a measure of resistance to flow) will be lost in compressing the bubbles. The OEM may have had plenty of reserve capacity, but not for the increase.

You may see a slight improvement running at the top of the tank capacity, as that should give a little more settling time for the gases to escape, and there are specialist products that can be fitted in the return to tank to aid air-oil separation, if you suspect this is the problem, the SPINTRIC - I was also going to suggest it, not an endorsement, never used it - may be useful, but even a simple baffled swirl tank, vented to the dry sump tank(?) may be beneficial.

Of course, could be something completely different, like the engine not being properly scavenged (checked the pick-up filters?), and the oil level dropping too low in the reservoir, or the pressure pump cavitating?