<VV> Oil Pan Windage Tray

[Sethracer at aol.com]

In a message dated 3/24/2006 8:31:54 PM Pacific Standard Time,  
bgilbert at redshift.bc.ca writes:

Ok, I  have to ask - what is a windage  tray?

Bob




With engines where the crankshaft rotates just above the oil sump, like  
every Chevy V8 made since 1955 - except the new Z06 motor - the oil flowing off  
the crank make what looks like a hurricane of oil and air mist, all around  the 
rotating assembly. Starting with the 1967-69 Z28 motor, probably the  highest 
revving Chevy engine ever sold to consumers, they installed a  slightly bent 
tray on stand-off bolts where it would live just between the  outside most 
rotating point of the crank/rod assemblies and above the oil level  in the sump. 
This "Windage Tray" had louvers punched in it - although  aftermarket types 
take many designs - the tray louvers grabbed the oil that is  flying around (in 
windage) and scrapped it down into the sump. Since then things  have gotten 
much more sophisticated. Crank scrapers are fitted to the sides of  the oil pan 
and trimmed to strip any excess oil off the rotating assembly -  fitting as 
close a a few thousanths of an inch. The goal is to keep the rotating  assembly 
spinning in oil free air, thus providing less drag to rotation, and  more 
horsepower. It also provides better oil control and probably longer life.  But 
these are after all race motors. Most real race motors use a dry sump,  wherer 
the oil is pumped out of the pan (scavanged) and into a separate tank,  where 
air is removed. The oil is then pulled from the tank and pumped back into  the 
engine. The Corvair has, in essence a dry sump, because the oil pan has the  
cam located between it a the "crankcase", so oil cannot travel very far from the 
 sump - at least to the crank location. Of course the top of the Corvair case 
has  that same oil hurricane effect. The stock top cover has the same louvers 
that  the Z-motor used, but on top, aimed in the direction to help contain 
the  oil from the top breather. When the Corvair motor is reverse rotated, as it 
is  for some VW conversions, the top breather becomes critical, since the 
louvers  are now scraping oil up into the breather. That oil must be handled and 
recycled  into the motor somewhere.  - Seth Emerson