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windage tray

General engine tech -- Drag Racing to Circle Track

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statsystems
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Re: windage tray

Post by statsystems » Tue Jan 09, 2018 4:15 pm

ptuomov wrote:
Tue Jan 09, 2018 3:19 pm
Newold1 wrote:
Tue Jan 09, 2018 3:17 pm
Crankshaft scraper that looks like this. www.jegs.com/i/moroso/710/25830/10002/-1
What oil would there be on the crankshaft counterweights at 6000 rpm to be stripped by a device like that? ;-)

All the oil coming off the rods.

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Re: windage tray

Post by ptuomov » Tue Jan 09, 2018 4:18 pm

statsystems wrote:
Tue Jan 09, 2018 4:15 pm
ptuomov wrote:
Tue Jan 09, 2018 3:19 pm
Newold1 wrote:
Tue Jan 09, 2018 3:17 pm
Crankshaft scraper that looks like this. www.jegs.com/i/moroso/710/25830/10002/-1
What oil would there be on the crankshaft counterweights at 6000 rpm to be stripped by a device like that? ;-)
All the oil coming off the rods.
Strong arms those oil droplets have, holding on to the 3-5" crankshaft throws at 6000 rpm. That's 1000's of g's, or 100's x own weight. Like me doing pull ups with 10,000lbs of weights hanging on each leg. I've they are that strong, how will that sheet metal piece called scraper have any chance stripping them off? ;-)

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Re: windage tray

Post by Newold1 » Tue Jan 09, 2018 4:36 pm

They don't scrape against the rods or crankshaft counter weights, they are ground down to fit about .125" to about .060" off the bottom of the rods and the faces and sides of the crankshaft throws to release oil riding and dripping of those pieces and they work quite well at doing that. Only one is used on one side of the pan rail, between the pan and the pan rail of the block. Many engine builders and thousands of racers use them in engines at rpms as high as 8500 rpms. Have you never seen or heard of these before! I am surprised by that.

Google for images of crankshaft scrapers on engines, there will be lot of pics. for examples.
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Re: windage tray

Post by In-Tech » Tue Jan 09, 2018 4:42 pm

pt, how many pullups can you do at a slow speed meaning gradually 1 per minute at a RATE of 1 per minute, not 1 in a second each minute but 1 per minute slowly. Now change that to 60hz and you can do it. I bet you cannot do 3 in 3 minutes if based on my original question. Contemplation requires more effort. Time is a constant and that is how some people arrive at a result, not an answer. The scraper is a helper, not a constant.

Anyhoosit, nuff said and too many drugs this year with 4 surgeries since Feb, it just slows me down. [-X :mrgreen:
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Re: windage tray

Post by ptuomov » Tue Jan 09, 2018 4:47 pm

Newold1 wrote:
Tue Jan 09, 2018 4:36 pm
They don't scrape against the rods or crankshaft counter weights, they are ground down to fit about .125" to about .060" off the bottom of the rods and the faces and sides of the crankshaft throws to release oil riding and dripping of those pieces and they work quite well at doing that. Many engine builders and thousands of racers use them in engines at rpms as high as 8500 rpms. Have you never seen or heard of these before! I am surprised by that.
Sometimes I feel that I've heard almost everything by this point in my life...

Why do you need a sheet metal piece to "release oil riding and dripping of those pieces" when those pieces are being spun at 6000 rpm or so with a radius of 3-5"? Seems like they'd achieve the release on their own with the thousands of g's in acceleration, right?

It simply seems to me that the commonly stated purpose for crank scrapers makes no sense in light of laws of physics. They won't scrape anything off crankshaft. It doesn't need to, the crankshaft rotation violently throws off everything on its own.

The most sensible beneficial effect that I've heard a scraper has is that it sometimes prevents the oil that is thrown off on its own from the crankshaft from rebounding back to the crankshaft. I can see that being a potential benefit from that sort of oil deflector. I question the magnitude of that benefit, however, given that the truly high budget drysump systems don't have such deflectors. They just have the minimum volume crankcase, depressed atmosphere, separated bays, and a scavenge port in each bay.

For small displacement inline engines, those sheet metal pieces placed very close to the crankshaft may also do something beneficial for gas pressures around the crankshaft, although I'm not convinced.

For large displacement V8 engines, the piston pumping effects on the gas pressures are much larger than the crankshaft rotation effects, and anything that blocks those piston pumping pulses just costs power. For large displacement V8's, the factory engineers don't incorporate scrapers, keep the windage tray relatively far from the rotating assembly, and put large holes into the windage tray on one side. And I believe those trays cost a little bit of power on a stationary dyno, but make a lot of things better in the actual use when the engine is subjected to external g forces.

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Re: windage tray

Post by ptuomov » Tue Jan 09, 2018 4:49 pm

In-Tech wrote:
Tue Jan 09, 2018 4:42 pm
pt, how many pullups can you do at a slow speed meaning gradually 1 per minute at a RATE of 1 per minute, not 1 in a second each minute but 1 per minute slowly. Now change that to 60hz and you can do it. I bet you cannot do 3 in 3 minutes if based on my original question. Contemplation requires more effort. Time is a constant and that is how some people arrive at a result, not an answer. The scraper is a helper, not a constant.

Anyhoosit, nuff said and too many drugs this year with 4 surgeries since Feb, it just slows me down. [-X :mrgreen:
Think of any material that is strong enough to stick to say 4" stroke crankshaft's counterweight at 6000 rpm, and I'll show you a material that is strong enough to make significant damage to the sheetmetal scraper that comes to contact with it...

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Re: windage tray

Post by MadBill » Tue Jan 09, 2018 6:03 pm

Well, if nothing else, it's a widely-held mass delusion, shared by a number of O.E.M.s... :-k

A couple of references:
https://www.google.ca/search?q=OEM+cran ... 45&bih=885

https://www.crank-scrapers.com/

https://www.google.ca/search?q=the+tea+ ... e&ie=UTF-8
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Re: windage tray

Post by statsystems » Tue Jan 09, 2018 6:13 pm

Newold1 wrote:
Tue Jan 09, 2018 4:36 pm
They don't scrape against the rods or crankshaft counter weights, they are ground down to fit about .125" to about .060" off the bottom of the rods and the faces and sides of the crankshaft throws to release oil riding and dripping of those pieces and they work quite well at doing that. Only one is used on one side of the pan rail, between the pan and the pan rail of the block. Many engine builders and thousands of racers use them in engines at rpms as high as 8500 rpms. Have you never seen or heard of these before! I am surprised by that.

Google for images of crankshaft scrapers on engines, there will be lot of pics. for examples.

If your crank scraper is .060 away from the crank it has minimal effect. My IJ crank scraper has UHMW or similar that is makes its own clearance which is essentially a .000 fit.

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Re: windage tray

Post by Newold1 » Tue Jan 09, 2018 7:06 pm

I have not used one of Ishiharwa-Johnsons scrapers. I have read about them and the teflon wiping technology and it seems to work well. I will have to try one and see for myself. I know that all scrapers definitely seem to work best at certain rpm ranges and I worry that if I tighten scraper to throw clearances any tighter I could end up with metal in engine, a lot of creepy noises, unhappy engine owners and warranty work! With metal to metal possibilities I like the Horse Shoes and Hand Grenades" idea - CLOSE!
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Re: windage tray

Post by ptuomov » Tue Jan 09, 2018 7:48 pm

MadBill wrote:
Tue Jan 09, 2018 6:03 pm
Well, if nothing else, it's a widely-held mass delusion, shared by a number of O.E.M.s... :-k

A couple of references:
https://www.google.ca/search?q=OEM+cran ... 45&bih=885

https://www.crank-scrapers.com/

https://www.google.ca/search?q=the+tea+ ... e&ie=UTF-8
Which car factory puts a crank scraper in a modern crossplane V8? I don’t recall seeing any.

Almost all of them have fairly complex and expensive to manufacture windage trays, though. The trays are reasonably far from the crankshaft, and all have generously sized breathing hole area.

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Re: windage tray

Post by ptuomov » Tue Jan 09, 2018 8:46 pm

Newold1 wrote:
Tue Jan 09, 2018 7:06 pm
I have not used one of Ishiharwa-Johnsons scrapers. I have read about them and the teflon wiping technology and it seems to work well. I will have to try one and see for myself. I know that all scrapers definitely seem to work best at certain rpm ranges and I worry that if I tighten scraper to throw clearances any tighter I could end up with metal in engine, a lot of creepy noises, unhappy engine owners and warranty work! With metal to metal possibilities I like the Horse Shoes and Hand Grenades" idea - CLOSE!
The engine in my car has a heavily modified I-J system in it. It does solve a very specific problem with my engine very well. It's not scraping anything off the crankshaft, however.

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Re: windage tray

Post by Geoff2 » Wed Jan 10, 2018 3:11 am

ptuomov,
To answer your question about Chrysler windage trays: numerous publications. This is one from my Mopar Performance handbook, published by Chrysler: 'We ran the B-RB windage tray on our new 440 dyno engine. 400 hp without, 416 hp with tray'. Engine was run to 6000 rpm.

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Re: windage tray

Post by ptuomov » Wed Jan 10, 2018 7:52 am

Geoff2 wrote:
Wed Jan 10, 2018 3:11 am
ptuomov,
To answer your question about Chrysler windage trays: numerous publications. This is one from my Mopar Performance handbook, published by Chrysler: 'We ran the B-RB windage tray on our new 440 dyno engine. 400 hp without, 416 hp with tray'. Engine was run to 6000 rpm.
Interesting. I can see four immediate possibilities:
1) hp inferred from dragstrip et and mph
2) measurement error
3) crazy oil pan design, such as round ship-hull shape without sufficient depth
4) my thinking about windage trays is wrong

In modern V8 engines, the tray seems to reduce power in stationary dyno. This based on reading the papers and talking to and exchanging emails with people who design the software that is used to design windage trays.

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Re: windage tray

Post by BigBlockMopar » Wed Jan 10, 2018 3:08 pm

How about maybe that windage trays on modern days engine are installed closer to the crankshaft than on older engines?
Or larger internal block webbing? Providing less room for air displacement/movement between cylinders.

Another thought; how about the thicker oils used in the older engines would show more benefit with a tray in draining/keeping the oil away from the crank than on modern engines with thinner oils.

Then again, why would modern manufacturers spend the resources to design and fabricate something that will limit its engine power.
There must be more (economy/efficiency?) benefits at the lower rpms that offset a little loss in the upper ranges I would think.

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Re: windage tray

Post by Curtis Mc » Wed Jan 10, 2018 3:23 pm

bigblockmopar wrote:
Wed Jan 10, 2018 3:08 pm
Then again, why would modern manufacturers spend the resources to design and fabricate something that will limit its engine power.
There must be more (economy/efficiency?) benefits at the lower rpms that offset a little loss in the upper ranges I would think.
Exactly, let's not confuse high-performance aftermarket and builders with the OEMs. That being said, where there is crossover is with windage trays and dry sumps. OEMs do have the ability to build in oil control and crankcase breathing at the design/casting level - everyone else is trying to improve where they leave off.

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