Posted for "Maurits van Rooy" <mvr7@hotmail.com>:

 Gary,
 
 You are taking air of the high pressure port and it has to go through the
flow pack to reduce the pressure and increase volume before going into the
cabin like they do on a PT6, on the E model they made a special port on the
low pressure side of the compressor that already provides the correct pressure
and volume so you do not need a flow pack.
 
 Maurits