Aha! Thank you, David. 

Cunegonde is an 83.5 and has this baffle. 91 I just worked on does not. Which is correct according to list wisdom?

> On May 7, 2014, at 11:27 AM, David Beierl <dbeierl@attglobal.net> wrote:
> 
> At 02:01 PM 5/7/2014, Cunegonde wrote:
>> This part doesn't appear in Bentley, unless it's a non-pictured part of the heat exchanger itself.
>> 
>> Inside the heater box, sandwiched between the core and the blower manifold openings, is a piece of sheet metal that doesn't quite cover the whole face of the core . It has one row of small holes along one long side, and three rows of holes along the other long side. It obviously blocks large debris, but also restricts airflow to about 50% of the core.
>> 
>> What is it, and can I leave it out for greater heat exchange efficiency?
> 
> p/n 251 265 329.  VW call it a baffle plate.
> 
> When I see odd stuff like that I tend to suspect that it was introduced after the initial design to solve a problem that showed up in testing.  If I had to guess, I'd guess that they weren't getting enough temperature rise in the air going through the core, so they slowed it down some.
> 
> Yours,
> David
> 
>