Date:         Sun, 7 Mar 2004 07:57:30 -0800
Reply-To:     Michael Snow <slowmachine@COX.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Michael Snow <slowmachine@COX.NET>
Subject:      Re: 300 miles with a tank...
Comments: cc: Gnarlodious <gnarlodious@EARTHLINK.NET>
In-Reply-To:  <BC708341.38642%gnarlodious@earthlink.net>
Content-Type: text/plain; charset=us-ascii; format=flowed

>>>I got you beat, at 39 MPG (highway) I get over 400 miles between fillups. Of
>>>course, I see more than my share of middle finger salutes (1.6 diesel).
>
>>Are you sure it isn't*29* MPG?
> Nope, 39 on the nubbin.
>
>>BTW, what is the altitude where you live?
> I live at 7200 ft, why?


There have been many discussions of diesel Vanagon fuel economy on this
list and others.  These vans consistently average 25-30 MPG.  My
personal best, so far, has been 29 MPG.  This was averaged over a 900
mile highway trip.  Older VW diesel cars using the same 1.6D engine, at
half the weight of a Vanagon, typically average around 45 MPG.  For
these  reasons, I suspect that your 39 MPG is an anomaly or miscalculation.

Altitude, and the corresponding air density, are important factors in
non-turbocharged diesel performance.  When I take my diesel van from San
Diego (sea level) to northeast Arizona (8000 ft), performance and fuel
economy suffer greatly.  My injection pump (calibrated at sea level)
produces embarrassing clouds of black smoke if I give it too much fuel.
  This becomes very noticeable at 3000-4000 feet and gets worse as I
climb.  I've actually been stopped by the California Highway Patrol for
doing this at night when I could not see the smoke.  Once they figured
out it was a diesel, they laughed and sent me on my way.

Your MPG number makes me wonder what results I would get if I
recalibrated my injection pump when I arrived at altitude instead of
compensating for the altitude difference by using a little less "right
foot."  I'm also considering having a pump built with an altitude
compensation mechanism for this purpose.

Michael Snow
1982 Westfalia 1.9D
1986 GL
1987 Syncro GL