Don,
The rear pillar vents only allow air to enter the engine compartment area, 
They were used for the air cooled vanagon to pull fresh cool air into the engine compartment which had a rubber seal
To keep the hot discharge air from re entering the engine compartment.   All air cooled vws and porsches have had a seal around the engine. 

Now they serve the air box on the right and just pull in cool air on the left for the wbx engine. 

Only way to vent is install the 88 on vents behind the windows.

Doug

  ----- Original Message ----- 
  From: don spence 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Tuesday, June 08, 2004 9:56 AM
  Subject: Re: heater controls

  If the description below is accurate, what is the purpose of the rear 
  pillar vents?

  So far we have only discussed how air ENTERS the vehicle. But of 
  course, no air can come IN unless air goes OUT. This is called 
  �flow-through ventilation� which all vehicles have to some degree. 
  Prior to 1988, if all windows were closed, the only way air could get 
  out was to exit through little exit vents located on the rear lower 
  corner of the front door interior panels. These are the plastic vent 
  assemblies with the little blue slide lever. These vents allowed air to 
  exit the interior. Sliding the lever toward the front of the vehicle 
  opens the vent, rearward closes it. On the leading edge of the doors, 
  in the door jam, there are three oval holes that open into this hollow 
  space of the door itself. As a Vanagon plows through the air, air flows 
  around the vehicle creating low-pressure zones near the front door jam 
  areas. VW engineers realized this and used this low pressure to suck 
  air out of the interior of the vehicle. Air flows from the inside of 
  the vehicle through the little vent at the rear end of the front doors, 
  through the hollow door itself, into the door jam area, and out of the 
  body gap between the front door and front quarter panel. Genius, you say
  On Monday, June 7, 2004, at 07:40  PM, Automatic digest processor wrote:

  > Subject: Re: heater controls
  >
  > If you Google it, you'll find:
  >
  > http://www.gowesty.com/flow-thru_ventilation.html  and
  > maybe others.  M