Excellent, some actual testing results.
  Don Hanson

The second idea worked well and is a real solution. The open underside of
th=
e vanagon is a real drag component. We got a set of thin 0.0625 inch Al
shee=
t stock and enclosed (frame rail to frame rail) and basically covered the
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derside from the front to the transmission. We added louvered slots for
the=20=
radiator air flow, left the spare tire cover operable and stayed away from
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uspension components. Big decrease in drag - minimum 8% max 15%. 15% came
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en we added the Diesel sound box cover. Serviceability was a problem. The
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stem has been removed as I complete the front to back dual muffler system
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r the TDi and the diesel fired heater. No temperature measurements, but we
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rovide for air inlets at front by gas tank and at egress at the rear. Work
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n progress.

Frank Grunthaner=C2=A0