Eagler's Nest

Engines => 2 Cylinder => 1/2 vw => Topic started by: bill utt on January 25, 2014, 04:39:28 PM

Title: Windage tray
Post by: bill utt on January 25, 2014, 04:39:28 PM

Norm,
Don't forget a windage tray. I believe you will see even more improvement.
Bill

Title: Re: Windage tray
Post by: rockiedog2 on January 26, 2014, 06:17:55 AM

what is a windage tray?

Title: Re: Windage tray
Post by: Jlwright on January 26, 2014, 08:34:09 AM

Here is a link to one type.

 http://www.thesamba.com/vw/classifieds/detail.php?id=732507 (http://www.thesamba.com/vw/classifieds/detail.php?id=732507)

Title: Re: Windage tray
Post by: bill utt on January 26, 2014, 10:31:41 AM

Imagine looking inside of a crankcase, watching the crankshaft and connecting rods doing 3000+ RPM.
The air inside the case, with all that mass moving about is very turbulent, then add the oil that is being tossed every where.
All that sets up a tremendous amount of induced drag, that requires the engine to work against beside the outside forces it is trying to overcome. The windage tray keeps the oil from being picked up by the  disturbed air and flinging every where it is not needed, reducing drag internally.
Hope this helps, maybe someone can or will explain it better than I.
The tray is one of the reasons my 1835 can swing a 62x30. My mouse motor ROARS!
Bill

Title: Re: Windage tray
Post by: Steve on January 26, 2014, 12:48:13 PM

Bill:
Crankcase pressure and windage is something Joe Spencer & I worked all of 2013 and failed... The strategy was to lower the pressure in the case and consequently the windage friction...

We were tapping a single exhaust stack on Joe's 1/2 and found that the system needs more pulses than come from a single cylinder... See the probe next:

(https://www.eaglersnest.com/forum/gallery/3-260114143339-2071658.jpeg)

There are several companies on the net working on this process - in aviation Antisplat, and Moroso in automotive... I'm quite sure the guy's running 2-1 exhausts on the 1/2's and for sure a 4-1 on the 4 cyl motors can find gains with this setup:

http://antisplataero.com/Crankcase_Vacuum_Valve.html

(https://www.eaglersnest.com/forum/proxy.php?request=http%3A%2F%2Fantisplataero.com%2Fimages%2Fbc299ec3e735fc6719279a28837e42e9_diu5.jpg&hash=8fa4e91177393da8e5deba12d6677fb4108b0f0e)

Van's AF Forum  VAF has a number of posts on this product...
Steve

Title: Re: Windage tray
Post by: bill utt on January 26, 2014, 01:10:20 PM

Steve, the way I see it is pressure and windage are in fact, two different occurrences. Pressure due to compression leaking past ring end gaps along with the pistons acting as a pump while vented to the atmosphere. Windage due to solid items moving through the air within the case,causing a disruptive disturbance that lifts oil from the sump. Now the moving parts are encountering heavy fluid suspended in the air.
Hope I am not to far off on this explanation. It is from my drag racing days in the sixties.
Bill

Title: Re: Windage tray
Post by: Bob S. on January 26, 2014, 03:38:49 PM

Tray is a GREAT Idea! Wish I had that when I had my case apart!  Didn't know that was available for a normal VW.... Will get one for my NEXT 1/2 project.

Title: Re: Windage tray
Post by: Steve on January 26, 2014, 05:26:21 PM

Quote from: bill utt on January 26, 2014, 10:31:41 AM

Imagine looking inside of a crankcase, watching the crankshaft and connecting rods doing 3000+ RPM.
The air inside the case, with all that mass moving about is very turbulent, then add the oil that is being tossed every where.
All that sets up a tremendous amount of induced drag, that requires the engine to work against beside the outside forces it is trying to overcome. The windage tray keeps the oil from being picked up by the  disturbed air and flinging every where it is not needed, reducing drag internally.
Hope this helps, maybe someone can or will explain it better than I.
The tray is one of the reasons my 1835 can swing a 62x30. My mouse motor ROARS!
Bill

Bill:
This technology is was around way back in the Midget racing circuit:

http://www.daymotorsports.com/prodindex.php?g=~Engine~Valves%20%26%20Valve%20Covers~Valve%20Cover%20Components~ (http://www.daymotorsports.com/prodindex.php?g=~Engine~Valves %26 Valve Covers~Valve Cover Components~)

I way I see it is oil can't fog up in air that isn't in the case anymore - and doesn't suspend well in  lowered vessel pressure - the windage tray is a great starting point but there is more especially if you have the HVX mods putting more oil out on the rocker assys . . .
Just say'n:
Steve

Title: Re: Windage tray
Post by: bill utt on January 26, 2014, 05:54:48 PM

I agree with better venting of crankcase.
However,with wet sump engines the purpose is to separate the oil from the crankshaft.
We all know that VW's are wet sump.
Dry sump and scavenged engines don't have the problem.
Not just opinions but has been proven many times over.
If it didn't create more weight and complexity, I would have dry sumped my engine!

This does a better job of explaining than I did.
http://forums.moparmusclemagazine.com/70/7141434/mopar-engines/what-is-a-windage-tray/ (http://forums.moparmusclemagazine.com/70/7141434/mopar-engines/what-is-a-windage-tray/)
Great discussion!
Bill
Harley has had a scavenging system for decades. To get the oil away from the crank and back to the tank.:)

Title: Re: Windage tray
Post by: Dan_ on January 26, 2014, 07:38:23 PM

One or two things...

• The crank is above the cam so is a long way from the sump.
• Gs keep the oil where it belongs in these little airplanes.  (no braking, lateral, or acceleration Gs like in race cars)
• 3600 is not "high" rpm.
• wind-age tray is extra weight.

http://www.shoptalkforums.com/viewtopic.php?f=15&t=122265 (http://www.shoptalkforums.com/viewtopic.php?f=15&t=122265)

Title: Re: Windage tray
Post by: bill utt on January 27, 2014, 04:36:01 AM

I feel that the meat of the discussion has moved toward the thought, that I have been pushing great increases of performance with the use of the tray. Not so! When trying to squeeze as much as possible from an Air cooled and oil cooled engine, the details are numerous and more involved than a liquid cooled engine..  I stated that the tray was just One of the reasons! ( IMO) for the ability for my engine to swing a larger prop than normal. Each detail is just a small gain in the efficiency of extracting the most from each power stroke without  exceeding the thermal limits of ANY air cooled engine.
To each his own. Get em flying Guys( and Gals) ;D
Respectfully,
Bill

Title: Re: Windage tray
Post by: Vince B on February 24, 2014, 08:40:36 AM

WT vr`s HP , is it worth the extra WT in helping to gain some HP ? Not having the money to spend on a stroker motor you have to look at ways to gain power and for the cost of the Windage Tray it `s something to look into also in venting of crankcase will help with a few HP`s  .  8)  You will be running this 1/2 most of the time at  80% to full power it would not hurt to try this  .