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Enzo's Windage Plate Is On!!!


Enzo

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Glad you found it helpful Enzo. You might want to make the first one out of plastic. It might be cheaper and you can still check the fit. I'd use a gasket for the initial dimensions, that gives you most of the layout.

 

eMachines might have somebody to help you get the drawing right the first time.

 

Keep us posted!

 

Frank

 

 

 

FRANK!!!

 

What a kick ass idea!  Wow, great web site!  I didn't know this stuff could be done on line.

 

Here's what I'm gonna do - order one with the correct inputs and dimensions.  It will be pretty fun.  Then we will lay it on Greg's V11 at home to see if it fits.

 

And, if I can do THAT, I can take on other projects.  Vedy vedy interestink.

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Guest Fonzarelli

This plate actually looks more like an oil pan baffle than a windage tray. I do not believe that the oil is close enough to the crank to whip the oil into a foam.

 

Like AJ mentioned, a windage tray or scraper, is positioned very close to the spinning crank to deflect spinning oil back into the pan.

 

The windage scrapers do also cut down on the oil vapor that the crank would be subjected to hitting at high RPM. Ever stick your hand out the window at 60 MPH? There is a lot of force against your hand with just wind, just imaging if there was a heavy oil vapor present. That is where the benefit is.

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Fonz,

 

This plate actually looks more like an oil pan baffle than a windage tray.  I do not believe that the oil is close enough to the crank to whip the oil into a foam.

 

The crank is not close to the oil in the sump as you say. But I think what happens is that the spinning crank creates a vortex. This vortex is a low-pressure system which SUCKS UP the oil in the pan into the maelstrom. (Hey, that sounds like a song, 'Into the Maelstrom.')

 

This suspended oil is simply thick wind resistance to the crank. Also, it is not in liquid isolation waiting to do its job in the sump.

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I remember reading what he wrote about seeing high speed films that GM had on what he called "windage" and how oil coming off the cam crank and drains would ball up and float around the crank at high rpm's due to the vortex created until it was hit. Then it would reform on the walls of the block and do it all over again. He built wipers that were cut to match the crankshaft profile to scrape the floating oil off and get it to go into the sump..

Great book if you can find it.. very heavy theory but great book.

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Chris Rampen, who some of you may *know* from the Oz forum has spoken a lot about this and the development of windage trays in general. I did a bit of hunting and found some time-lapse/ strobe pics of an operating crank with the sump off and it was fairly amazing!

 

On the subject of cooling and lubrication though just think about what needs lubricating and what gets hot!

 

The bearings need lubrication, at pressure, to form a decent hydrodynamic wedge to protect the bearings and oil flow to remove heat but this oil is delivered, directly to them by way of the galleries, none of the bearings per-se are lubricated by splash, even Guzzi have gone beyond the Briggs and Stratton principle of a dipper-spoon on the rods :D !!!!!

 

The bits that will most need lubricating are the little ends and the cam lobes. Look at where they are and you can see that oil flung off the crankpin through the side clearance on the rods will do a more than ample job.

 

Pistons are mainly cooled by conduction through the skirts and a lesser extent through the gudgeon pin. (Bear this in mind when looking at the supposed *performance* aftermarket pistons, especially the FBF units which to me look like their thrust faces are too short and these are what generate more heat rather than dumpng it.).

 

Sorry, I'll come back to this, gotta go, it's supper time :food: !

 

Pete

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Continuing, (Belch!) the cam lobes are not pressure fed on any motor I'm familiar with. Some of them may have oil jets directed at the cam but the wedgeing action on the oil is a result of the oil that gets deposited on the lobe by splash and the rather extreme forces that act on the face between flank and follower during the opening sequence. At anywhere aproaching moderate RPM the need for protection on the closing flank diminishes as the force exerted by the spring will, effectively, diminish with a rise in engine speed.

 

All the oil that gets flung off the crankpin will come off in great streamers directly at the area of the camshaft where the lobes are located, belive me, there is MORE than adequate oil there! Guzzi themselves have used a variety of connecting rod designs over the years. Some have no oil squirters in the rods, some have squirters on both sides of the shank and some have squirters only on one side! ALL replacement big end shells have two oil feed holes in them which to me would imply that a.) Guzzi haven't worked worked it out at all. b.) Whoever was given the job of drilling the rods was an idiot or lazy, or c.) It was just rabid conservatism on the part of the designers who were, periodically, given the task of making any damn chage they liked as long as it was CHEAP!!!! :D My Carillo roda don't have squirters and they've never caused my pistons to melt. Why? Perhaps because enough oil gets flung up under the pistons to render them un-necessary, neither do the Argo's e are using on the new racebike motor and belive me I don't worry at all about lack of cooling or poor lubrication on that, only on it not emptying it's sump all over the rear wheel, (Although by *law* we have to run a catch bottle.)

 

Look, I heartily respect Mike Rich, in fact I Rob and I are thinking of sending the racebike heads to him at sometime soon-ish when we can afford it, but on this one, especially in a roadbike application, I think he's got it wrong. That's not to say I'm *right*, there are always many ways to skin a cat, but I think his fears are unfounded on this one.

 

pete :thing: (Dunno what that is, but I like it :grin: )

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What was the failure Ed experienced Todd?

 

Pete, not sure... I thought you two would have chatted about this when you were stateside. Contact him direct if you'd like; EdGuzziTech.com

 

Mind you, I'm not "downing" the windage/slosh plate, just I personally think it's a waste of time and money unless your racing your new V11S.

 

I'd challenge ol' Enzo to any form of competition he'd like, including back to back dyno pulls on a Dynojet 250i air/fuel dyno. Hell, I'll even monitor oil temp since we both have (OEM) oil coolers.

 

My $.02,

ToddGuzziTech.com

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...indeed, I as well am not offering a definitively negative opinion on the WP application, as I personally have no data/experience to present for either position.

 

I am only passing on what info I have been told :huh2:

 

 

I am interested to see how this develops over time.

 

al

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Hi,

 

Lets assume for a while that a windage plate itself will not cause any lubrication problems, but the lubrication is really taken care of by the pressurized oil feed travelling through the crank, cam, rods etc. Some of this oil (after exiting through the bearings) will splash around to lubricate cam chain and otherimportant items before returning to the sump. In other words, we do not need any oil splashing directly out from the sump to lubricate anything. Sounds reasonable, right ?

 

Then, next question is that can a windage plate really free up some hp ? If not, it will only add some weight and that is bad -_-

 

For simplicity, lets assume now that the outmost parts of the crank are travelling around in a circle having 20 cm diameter (10 cm radius). This gives us a circumference distance of approximately 63 cm (2*pi*radius), if one thinks the smallest circle inside which the crank could turn. Engine running 5000 rpm, this means that we a peripheral speed of 0.63*5000 m/min = 3150 m/min. This equals to 52.5 m/s.

 

Ok, 1 m/s equals 3.6 km/h. Now we see that 50 m/s = 180 km/h !!!

This means that at 5000 rpm the outmost parts of the crank are travelling faster than 100 miles/h. If those parts move repeatably and closely over the surface of hot oil in the sump, it seems that the vortex created there can really lift some of the oil airborne and cause foaming etc. Imagine any object (with that size) passing by your face less than 10 cm away and having speed > 100 miles /h.

 

The airborne oil will also surely create a drag / resistance when moving the crank at that speed. This might at high rpms require a noticeable amount of hps to be overcome.

 

It seems that the benefits of a windage plate could be maximized by locating it as close to the crank as possible, but this is technically quite challenging in a guzzi. Still, some clear benefits could be there just by covering the sump in a way Enzo's plate is doing.

 

br, JuhaV

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For simplicity, lets assume now that the outmost parts of the crank are travelling around in a circle having 20 cm diameter (10 cm radius). This gives us a circumference distance of approximately 63 cm (2*pi*radius), if one thinks the smallest circle inside which the crank could turn. Engine running 5000 rpm, this means that we a peripheral speed of 0.63*5000 m/min  = 3150 m/min. This equals to 52.5 m/s.

 

Ok, 1 m/s equals 3.6 km/h. Now we see that 50 m/s = 180 km/h !!!

 

It seems that the benefits of a windage plate could be maximized by locating it as close to the crank as possible, but this is technically quite challenging in a guzzi. Still, some clear benefits could be there just by covering the sump in a way Enzo's plate is doing.

 

br, JuhaV

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I was planning on doing the calcs when I had a spare moment but you've got in first, thanks. It's alsp worth remembering that the crank itself is a bloody great irregular shaped piece of steel that is in no way aerodynamic so drag is going to be *up there*!.

 

Yes, ideally a propperly designed plate to maximise the efficiency should have web scrapers and screens but this would require a lot of farting about. A large amount of the benefit can be achieved simply by 'dry-sumping' the engine with a plate such as Enzo's, this isn't a new idea, it's been around for many years on Guzzi big blocks and is known to cure the breathing problems on older machines. The baffling effect of the plate will also be very iseful on the broad sump models, (And yes, the Sport Corsa is essentially the same internally as the V11 motor.) which have the nasty habit of exposing their oil pick-ups.

 

Pete

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It seems to me that windage plates are just a fix for the real problem (if there is one).

Has anyone put knife edges on the crank to reduce windage?

One related point- remember it's the back of the crank that would cause any disturbances. As it whizzes around at speed, there's a vacuum that follows the flat crank weight. That's what sucks up oil (if it really does).

Also- if you do make a windage plate, you might want to remove those points on it- isn't that what causes stress fractures?

 

J

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JuhaV,

 

Brilliant work! Your calculations help illustrate what is going on here. Once again, I encourage others to try the plate. It makes a noticeable improvement on acceleration. I want others to verify this for themselves.

 

I will be sending the drawing we came up with back to Pete. He was kind enough to send me a plate for testing. I like its size. It is 2mm thick and about a pound and a half. No bid deal! I like that something so critical is not fragile.

 

If you are interested in the plate, contact Pete Roper. He deserves the credit and the shekels.

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"Has anyone put knife edges on the crank to reduce windage?"

 

When I had my engine lightened and balanced, it was knife edged. Here are some picts.

 

Enzo. "A" for effort, but may I suggest a more scientific method?

 

Back up the claims with some good dyno results. use the SAME dyno before and after mods. I really want to believe your exhaust did something but going to a different dyno voided any real proof.

 

I would also think that a windage tray may help at extended high speed running (like 8000+ rpm)

This would show up only on the dyno as a gain in the upper parts of the rev range....I don't think you would gain anything at lower revs.

 

"ass" dynos are really not that accurate.

 

Keep it up, you might be on to something.

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