[200q20v] Audi 20V Turbo Crankcase Breather System Tunin g

[tommy.arnberg at nokia.com]

Hello !

Some new comments.

- vented = the pressure gets out of the system 
 to free air somehow
- the pressure has to come out, otherwise...BANG and oil every where...
- it can be done several ways:
  * burning in the engine near the valves (Factory method)
    (by the way, imagine how the burned black stuff enters the CATs...)
  * letting the crankcase and valve cover fumes into free air
    (this is illegal, but...)

- the carbon canister system MUST be connected to inlet manifold
   but doing so that the black back flow preventing valve (part number 6)
   http://www.egroups.com/files/Audi20V_Kruemmer/Crank_bre_3B.ppt
   is taken out of use and connection closed at end of #11

   This could be the new system (page 2 and 3)
   http://www.egroups.com/files/Audi20V_Kruemmer/Crank_breath.ppt

- Carbon canister fumes are needed during vacum (idle also)
  conditions to make the mixture richer. 

> Anyway,  Tommy A. seems to believe the device should be  a _vented_
> oil-separator, whereas I had assumed that any oil collection 
> device would  need to maintain the closed crankcase breather system. Tommy

> says (of the bottle w/vented cap):

> >This "vented thing" is very handy and important because
> >the oil/air -pressure has to come out of the system
> >when the original connection to Turbo charger
> >input is disconnected !  And the bigger the
> >hole is the easier is the pressured air to come out !
> 
> My own naive view is that you need to maintain a closed loop 
> and just take  out as much oil as possible from the crankcase air flow 
> before it reaches the MAF, turbo, IC, MM-hose or IM. Seems to me that the 
> "vented" approach will have inherent problems 
> (unmetered air, carbon canister fumes, etc.)

It would be ideal to have perfect separator and collector 
and averything in closed system. I hardly belive that it would be "optimal"
from high boost point of view. When optimal it would be much better 
than the factory solution !  
 
> whether or not the oem crankcase pressure regulator is at fault if
> excessive quantities of oil are observed ....

I do not belive that the oem crankcase pressure 
regulator is fault because it does not prevent the 
Oil fumes getting into the valves
- the pressure goes either through Turbo (high boost condition) 
  or  when in vacuum condition then through
  back flow valve #6 and rubber hose #11 or #11a
   to inlet manifold and then to valves
- during boost the valve #6 is closed  
  (try to blow air through it the other way !)
  (when pressure at both sides of #6 then the net flow direction is tricky
!)

In the factory system, when connected correctly there is a part of 
"poorly metered air", during boost.  I assume that, when the extra air/fuel
goes 
through crankcase breather system the mixture is not corect any more
for reburning. The main mixture gets ~leaner when  A LOT  of crankcase
 fumes get into Turbo and further back to valves. This applies for older
engines
 with high boost.  

This is not so simple thing and I would like to hear some comments  !!

Regards, 
Tommy