Date:         Mon, 30 Nov 1998 16:33:09 -0500
Reply-To:     Martin Jagersand <jag@CS.YALE.EDU>
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Martin Jagersand <jag@CS.YALE.EDU>
Subject:      Re: Vanagon total drag and mechanical losses
Comments: To: satcong@vol.com, vanagon@vanagon.com
In-Reply-To:  <3661F5B3.43DC6A99@vol.com> (satcong@vol.com)

Thanks for the note Bob. A wind tunnel test of air drag
would certainly be cool. VW probably has done one. Just a matter
of getting the right publication.

Practically I think total drag is of more value, and accuracy
to fractional kW or hp is not a concern. Our vehicles vary
a lot anyway. Campers, transporters and double/sighle cabs
will all have different wind drag. All vehicles will have
rolling resistance varying with tires (BIG difference! See the
archives for an evaluation I wrote some years ago)
tire pressure, how good shape suspension and brake parts are
etc. I'd guesstimate that we should be happy with a 10% error margin.

Road and track used to publish drag figures. Is that possibly
where you got yours from? I saw some for a synchro. I also
have notes with similar (but not exactly the same) figures as
yours somewhere (check my WWW page). Aslo unfortunately can't
find my reference right now.

I'm cc:ing this to the list as other people may be intertested in
the data.

  Speed  Power
  (km/h)  (kW)
    30     4
    40     6
    50     8
    60    10
    70    13
    80    16
    90    20
   100    23
   110    27

/Martin
--
Martin Jagersand                 email: jag@cs.yale.edu
Computer Science Department             jag@cs.rochester.edu
Yale University

        Slow down and visit the VW diesel Westy page:
          WWW: http://www.cs.rochester.edu/u/jag/vw
-------------------------------------------------------------------

   Martin - A far more reliable indicator would be just the placement of a
   Vanagon in a wind tunnel, like the one down in Marietta, GA.  Interested
   in donating some $'s?  $3000/hour, via appointment, of course.

   Seems like I ran across a graph on the Net of Vanagon drag, but have
   been unable to relocate it.  Best I remember, it takes something like
   12hp@40mph, 30hp@60mph and 80hp@80mph.