David, I think the metal pipe to the air cleaner is much of your
problem. I bet the turbo noise carries in it and then resonates in the
cavity where the air cleaner protrudes. I used wire reinforced rubber
hose on my AAZ conversions and turbo noise is not a problem. I used 3
different air cleaner configurations, all attached to the body in that
space behind the tail light and connected to the turbo with rubber hose.

Mark

David Marshall wrote:
>
> I love my converted 1.9TD Westfalia with the exception of one thing - the
> whistle of the turbo charger.  What have other people done for the air box
> on their turbo vans?
>
> My intake system is a very simple setup.  It consists of a 2.0" piece of
> muffler tubing that is bent at 90 degrees the end that attaches to the turbo
> charger was reduced to 1 7/8" to mate up with the turbo inlet - I used some
> hightemp silicon hose and stainless camps to mate the turbo to the pipe.
> The other end of the pipe was enlarged to 2 1/4" so I could fasten a cone
> style K+N filter to it.  This filter sits in the area behind the driver side
> tale light and there is a piece of fiber glass isolating this chamber for
> the heat of the engine compartment so the K+N can only draw cold outside
> air.
>
> It idle, things are good, inside is quiet and if you stick your ear next to
> the driver side intake vent you can hear a slight whistle from the turbo.
> One you get this thing on the road it is a totally different story.  That
> turbo is very loud in side the vehicle - especially a part boost.
>
> What have people done to keep the noise levels down?  I like that whistle of
> power but this is a bit too much for me!
>
> David Marshall
>
> Fast Forward Automotive Inc.
> 4356 Quesnel Hixon Road
> Quesnel BC Canada  V2J 6Z3
>
> http://www.fastforward.ca    mailto:sales@fastforward.ca
> Phone: (250) 992 7775        FAX: (250) 992 1160
>
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