Date:         Mon, 23 Feb 98 20:53:28 CST
   From: Joel Walker <JWALKER@UA1VM.UA.EDU>
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   On Mon, 23 Feb 1998 19:24:07 -0500 you said:
   >So fuel consumption at full load and 4500rpm is:

   4500 rpm?? in a diesel??? isn't that pretty damned high?? i mean, i don't
   even run my gasoline/benziner at that rpm!!! that's almost 80 mph in my
   88 GL gasoline!! surely you mean a lower rpm???

The older D and TD's in the T3 was governed at 4800rpm. Newer ones
are 5350rpm. Engine does not like this for prolonged periods!
Up to 4000rpm seems ok for a long time.

   >= 5.34 gal/h

   that's terrible! my 88 gets 20 mpg at 60 mph which is THREE gallons per
   hour! :( at 70-75 mph, it gets about 16 mpg which is 4.7 gal/hour. something
   ain't right here with the calculations. ???

That figure is for the TD at 50kW (70hp). The relevant figure is the
3.9gal/h at 50hp (70-75mph).

   >At 60 mph: 26 mpg

   ?? that's not as good as the old 4-cylinder diesel in the 81-83 vanagons.
   they used to get 28 mpg on highway at 60 mph.

26mpg is assuming worst efficiency of engine. Yes, in practice
figures vary between 25 and 29mpg.

   >leap in confidence we can predict that given suitable
   >gearing target milage for a 1.9l TDI powered T3 Vanagon
   >would be about 32.5mpg. Of course changing driving

   ok, now that's better. can't figure how you got it, but ...  :)  i figured
   it would be about 35 mpg (SWAG ...stupid wild-ass guess) just based on
   weight versus the Eurovan and the Passat.

The calculations focused on steady state driving on flat ground.
Weight plays more of a role in accelerations (and uphill of
course!). However, with the power of the regular diesel accelerations
are, shall we say "discouraged" anyway, so the approximation
of steady state driving is not so bad after all. For a GTI driver,
who sees every stoplight as a race things are of course different.
But those don't tend to drive vanagons anyway.

/m
--
Martin Jagersand                 email: jag@cs.rochester.edu
Computer Science Department             jag@cs.chalmers.se
University of Rochester

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