Found this guy online.
might be worth a few HP for you NA guys
http://www.crank-scrapers.com/products.html
might be worth a few HP for you NA guys
http://www.crank-scrapers.com/products.html
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Potential HP increase?
- Thread starter whrdnsx
- Start date
Very interesting and shouldn't be hard to make, should be a nice addition to the baffles.
Next step from that would be dryslump
Next step from that would be dryslump
if you read further into their "What a crank scraper is and other technical info" they discuss this. Apparently a windage tray does not perform the crank scraper function...
Thanks. I'm reading it now. Looks like an interesting bit of hardware and it makes logical sense.
Not sure if I'll be an early adoptor though.
Perhaps some other mechanical engineers can chime in, but here are my thoughts.
First, I'm pretty sure he's not using his reference to the Tea Leaf Paradox correctly at all. The Tea Leaf Paradox, refers to a very unique phenomenon which occurs when the specific weight of an object relative to a certain centrifugal force create a state where the forces balance and the suspend the particles at the center of the vortex. (It's not really a paradox at all.) However, once the centrifugal forces change (crank speed changes), or the mass of the object change (oil particle size) then the balance is disrupted and the particles will no longer suspend. This is important to note because inside a crank case not only are the oil droplets varying in size/mass, but the engine speed varies wildly as well. Therefore it's almost impossible that oil would stay suspended in a "Tea Leaf Type Paradox" for any significant period of time. Therefore I feel as if the author is incorrectly stating the governing process. This, for me, severely hampered any credibility of what he wrote. What you really have is a cyclonic (like a Dyson vacuum) with all states of mass and centrifugal forces (crank speeds) which leads to a oily vapor mix (as he referenced as a cloud).
However, if you can overlook the fact that applies the wrong phenomenon to describe the oil cloud in a crank case, there are applicable statements and concepts in what he wrote. I believe that the crankcase scraper in actuality works very much like a baffle/separator plate/deflector plate in a centrifugal separator. In a centrifugal separator, high cyclonic speeds cause heavier particles to spin outwardly. If you can put a baffle/separator on the outermost edge, then you can capture particles. His referenced picture actually best demonstrates this.
For reference, here is a typical centrifugal separator:
In this way, the scraper is more of an oil baffle/collector, separating the oil from the air. So the question is, would this improve HP? While it's true that reducing the amount of free oil floating in the crank would reduce some drag, in my opinion it would be so minimal that it would result in negligible HP gains. Think about it, is it any harder to run in the rain than on a sunny day? Yes you are trying to push through each droplet of water, but it's significant? I think the baffle would help collect oil and return it faster to the pan, but again, it's a very negligible amount. Unless you need every drop of oil, your system is probably sized to compensate for this anyway. My take is this. Does it do what is intended to do? Yes, it should remove some of the oily vapor mix in the crank and return it to the pan. However, how much are we talking about? Very little. And is that enough to really make any difference at all? Not really. HP gains? Immeasurable. What it has going for it is that it is a passive device, it doesn't have any parasitic attributes to it; it's not going to hurt. It's like if I said, would washing and waxing your car help performance? One could argue that a smoother sleeker surface would contribute to less drag and air friction; but is it worth washing and waxing your car strictly for performance reasons alone?
First, I'm pretty sure he's not using his reference to the Tea Leaf Paradox correctly at all. The Tea Leaf Paradox, refers to a very unique phenomenon which occurs when the specific weight of an object relative to a certain centrifugal force create a state where the forces balance and the suspend the particles at the center of the vortex. (It's not really a paradox at all.) However, once the centrifugal forces change (crank speed changes), or the mass of the object change (oil particle size) then the balance is disrupted and the particles will no longer suspend. This is important to note because inside a crank case not only are the oil droplets varying in size/mass, but the engine speed varies wildly as well. Therefore it's almost impossible that oil would stay suspended in a "Tea Leaf Type Paradox" for any significant period of time. Therefore I feel as if the author is incorrectly stating the governing process. This, for me, severely hampered any credibility of what he wrote. What you really have is a cyclonic (like a Dyson vacuum) with all states of mass and centrifugal forces (crank speeds) which leads to a oily vapor mix (as he referenced as a cloud).
However, if you can overlook the fact that applies the wrong phenomenon to describe the oil cloud in a crank case, there are applicable statements and concepts in what he wrote. I believe that the crankcase scraper in actuality works very much like a baffle/separator plate/deflector plate in a centrifugal separator. In a centrifugal separator, high cyclonic speeds cause heavier particles to spin outwardly. If you can put a baffle/separator on the outermost edge, then you can capture particles. His referenced picture actually best demonstrates this.
For reference, here is a typical centrifugal separator:
In this way, the scraper is more of an oil baffle/collector, separating the oil from the air. So the question is, would this improve HP? While it's true that reducing the amount of free oil floating in the crank would reduce some drag, in my opinion it would be so minimal that it would result in negligible HP gains. Think about it, is it any harder to run in the rain than on a sunny day? Yes you are trying to push through each droplet of water, but it's significant? I think the baffle would help collect oil and return it faster to the pan, but again, it's a very negligible amount. Unless you need every drop of oil, your system is probably sized to compensate for this anyway. My take is this. Does it do what is intended to do? Yes, it should remove some of the oily vapor mix in the crank and return it to the pan. However, how much are we talking about? Very little. And is that enough to really make any difference at all? Not really. HP gains? Immeasurable. What it has going for it is that it is a passive device, it doesn't have any parasitic attributes to it; it's not going to hurt. It's like if I said, would washing and waxing your car help performance? One could argue that a smoother sleeker surface would contribute to less drag and air friction; but is it worth washing and waxing your car strictly for performance reasons alone?
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Meh. It'll take more evidence than, "it won't work" to offset the valid dyno plots and the scraper's implementation in race engines. Personally, I think a 2.5% increase in engine efficiency IS significant. Is 8-10hp negligible? Maybe not to some but the evidence of it's effectiveness (in the aggregate of data) and implementation is convincing.
It removes oil vapor/mist. Virtually inconsequential in one cycle, perhaps. But now multiply that by the amount of RPMs and then multiply that again by the specific points of contact (6). There you go...a 2.5% increase in efficiency.
It removes oil vapor/mist. Virtually inconsequential in one cycle, perhaps. But now multiply that by the amount of RPMs and then multiply that again by the specific points of contact (6). There you go...a 2.5% increase in efficiency.
I'm not saying definitively that it doesn't work, especially if it can empirically be proven through dyno test results. However, the explanation as to how it increases HP isn't very thorough or fully accurate especially when the wrong analogy is applied to the theory behind its operation. If they do result in a 2.5% increase in HP, then I feel there are more explanations and variables at play then just removing oil vapor clouds. Perhaps it's just a case of sound function, poor explanation. Although, higher displacement and/or higher RPM engines will multiply the effect exponentially due to affinity laws so perhaps there could be something there. However, the skeptic in me feels that the increase falls well within the +/- variability of dyno runs.
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