[Land-speed] Dry Sump Tank Questions...

[Bryan Savage]

My reply is below Mayf.
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On 10/19/2013 9:25 AM, Larry Mayfield wrote:
> I am considering the use of a dry sump system. Why? Well, the aspect 
> of fire caught my attention.  Ventilating the pan with a lot of oil at 
> full boogie makes a big mess and even bigger fire if it gets ablaze.  
> So, a smaller blaze with a small oil pan for oil collection only.
>
> If there is a link to something that can provide me with an education 
> on the kinds of questions below, I sure would appreciate it! I suspect 
> others would like it also!
>
> Just put your comments after the questions for me?
>
>  I see there are at least two different types of tanks: round and 
> square. Seems to me that a square or rectangular tank provides for 
> more oil than a round one of the same basic dimension, however, there 
> appears that there are more round ones than rectangular. Any idea as 
> to why? Seems like a flat sided one would be easier to locate and mount.
>
>
> I have seen some in catalogs with removable tops or panels, both round 
> and square and I guess that would be for removable of debris; but 
> seems to me that if debris is present in the tank then the pump is 
> probably toast.  So, why would a LSR team need a cleanable tank like 
> that?  Looks like another place to leak.
>
>
> Now, does the shape of the tank have anything to do with deareating 
> the oil returned from  the engine sump? Is round better for getting 
> rid of air in the oil? Why would that be?  Does the tank need a vent? 
> Other than the cap? I would guess 
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> so since air can be trapped in the oil as it goes though the engine 
> and it needs a place to escape.

WRONG!!!! AIR IS always trapped in the oil. The second most important 
job of a race car oil system is to remove the AIR
from the oil. This is second only to providing oil to the engine. Smokey 
did a lot of research and engineering on this subject.
He used tall round tanks that had round disks in the top for the 
returned oil to run across and deaerate. Of course the the returning oil 
entered the tank tangentially at the top of the tank.
The top of his tanks were vented to a low pressure spot on the car. I 
don't know where that was.
Smokey set up a test engine to find out how deep into oilpan the oil 
pickup had to be to suck up air free oil. Answer = 3 feet.
I heard of some attempts to evacuate the oil pan to reduce the air 
available. I don't know how well this has worked.
F-1  engines have used a main oil pump that contains a centrifuge to 
remove the air. A good plan if you have BIG bucks.
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//
> However, if a crankcase vacuum system is used though, would the vent 
> be required? Maybe a vent connected to the engine internally with a 
> hose so that air pressure is balanced everywhere?
>
>
> Should the tank be located below the pump to prevent siphoning or 
> draining back into the engine pan when the engine is off?
>
>
> For LSR type activities, are multi stage scavenge systems needed? I 
> have see some with pick ups in the lifter valley, the valve covers, 
> and the pan in two or more places.   Are pumps driven at engine speed? 
> Or under/over driven?
>
>
> Finally, pressure regulators.  Since oil is incompressible, then the 
> pressure regulator is also a flow regulator as well.  I have an 
> external NASCAR regulator on my parts shelf, but where to actually put 
> it in the system? Seems to me that putting it just after the pump is 
> draining flow from the engine. The "extra" oil being dumped could be 
> put directly into the pan where the scavenge system would return it to 
> the tank or actually plumbed to the tank directly: that seems better, 
> but, is it? What if the OP regulator is at  the last place to get oil? 
> Wouldn't that be an ideal place because that way oil is delivered at 
> full flow and pressure to those places that absolutely must have both 
> flow and pressure: main bearings and rod bearings.
>
> Standing by for any and all replies, no matter what they might be! I 
> get a lot of "you dumb f**k" so even those are ok.
>
> larry
>
> aka dipstick, dumb shit, idiot, no brains etc...