Date: Wed, 27 Mar 2002 09:41:53 -0600
Reply-To: Stan Wilder <wilden1@JUNO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1@JUNO.COM>
Subject: Re: Windage Trays and Lubrication Issues (Air and Water Cooled)
Content-Type: text/plain; charset=us-ascii
Thanks for your in depth response to the Windage tray.
Having many years of racing behind me I've purchased many $300.00 oil
pans, many dry sump systems and fabricated bunches of oil tanks.
Since I was racing in the 60s to late 70s things were not quite as
expensive as they are today.
In discussions with Bob Donalds we discussed stretching another ten
useable horsepower out of the Air Cooled Type IV engines.
Horse power seems to be directly related to money in the case of the Type
IV with each additional HP costing about $100.00 each over and above
standard short block rebuilding cost.
Your input about the Windage trays leads me to believe that the use of a
windage tray will improve engine performance and longevity with only
reasonable cost involved. Regardless of any HP gain I see that a stock
tray will build a better engine even without the very techno additions
used by professional racers.
I'm certainly not looking for it to give me ten HP but overall increase
engine life and be step one of working towards that desired ten HP.
Thanks
Stan Wilder
> 3. Add a windage tray. A good windage tray provides a barrier
> between the oil
> in the sump and the crankshaft lobes minimizing the amount of oil
> that can be
> whipped up by that flying crank. This eliminates the work done by
> the engine
> in overcoming the frictional mass and drag represented by the
> sheeting oil
> (worth about 5 hp in the VW crankcase. In addition, oil pressure
> will be
> higher, temperature lower and lubricity higher because of the lower
> level of
> dissolved gas. However, there are still sheets of oil clinging to
> the crank.
> In a good windage tray, like the VW one for the water-cooled inline
> 4
> cylinder engines, a set of cutters (or scrapers) are formed into the
> tray and
> run at a gap of about 1 mm from the crank lobes. The opening of
> these
> scrapers is oriented so crank rotation is towards the scraper mouth.
> These
> scrapers literally scrape the excess oil sheets from the crank lobes
> just
> like a clay potter shapes his work on the rotating table.
>
> 3A. Many professional engine builders find that the functions of
> windage tray
> and oil scraper should be separated and they use thick strong steel
> scrapers
> to run with a 0.010 inch clearance to the crank. These are followed
> by a
> windage tray with the extensive use of screen over open return
> paths. This
> screen deaerates the oil before it drops back to the holding sump.
>
> But this still doesn't treat the oil sloshing caused by starts,
> stops and
> turns. With a boxer engine, these issues can become critical as
> large amounts
> of oil can go to the pushrod tubes and the cylinder barrels.
>
> 4. This is handled by the use of baffles in the oil pan and, in some
> designs,
> by trap doors which protect the area around the oil pickup tube
> entrance.
>
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today! For your FREE software, visit:
http://dl.www.juno.com/get/web/.
|