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Date:         
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         ADMIN::KENNEDY      "William R. Kennedy, NJIT CIAT, 201-596-5648" 10-JUN-1996 16:13:40.61
Subject:      

I'd be glad if Eddy Lloyd's noise question turned into a long thread, as it
is one of the areas where the VW buses compare badly to the otherwise
insipidly unattractive competition.  First thing to do in addressing the
problem is figure out what noise component(s) we're going to attack.  I can
mention several.

Tires vary surprisingly widely in their noise level, and whatever noise they
make, the VW vans let a lot of it into the passenger cabin.  So new tires
may make it quieter.

Engine noise and transmission noise are significant, but not inexpensive to
deal with.  Different headers and mufflers have an effect, even tho' you
leave a lot of your exhaust noise behind you.  Interestingly, my passengers
indicate that the Porsche engine is quieter than the Vanagon engine it 
replaced, even tho the Porsche engine's muffler is pretty loud at idle.

The noise I would love to find an answer for is wind noise.  If I had a 
prepaid month to mess around I might play with some aerodynamics:  compare
noise level with and without mirrors, for instance, or with and without
modeling clay filling in the rain gutter by the front door leading edges,
or with and without a chin spoiler in front.

Whenever I have an interior panel off for any reason, I spray heavily with
undercoating on the back surface of the exterior sheet metal.  This has
failed to make my front doors sound like Mercedes doors.  On the plus side,
it means that there is no excuse for spending $16/sq.ft. for the stick-on
noise damping material, since it wouldn't stick on now.  Think of the money
I've saved.

What are others doing?
B.
Wm Kennedy
kennedy@admin.njit.edu