Date:         Mon, 03 Jun 1996 14:03:26 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         jwakefield@4dmg.net (john wakefield)
Subject:      TDI update News

Greetings,
  Those interested in following the Audi/VW company's new direct 
injection diesel motor series developments, may enjoy this latest mind 
candy.
  As earlier reported on this list, the 2.5L 5 cylinder version tested in 
1992 by Diesel Car magazine and later published in their October '92 
issue, was rated at 115 horsepower, or shall we say about 23 horses per 
hole.  In the large 3200+ pound A6 car it topped out at 125 mph, did 0-60 
mph in 10.7, and averaged 40 mpg while being driven hard during the test. 
They said to expect higher mpg in daily driving.  So you'd expect the 4 
hole version to come in around 23 horses times 4, and indeed the 1.9L 
showed up being rated as 90 horsepower.  Later versions of this 2.5 TDI 
arrived in a variety of vehicle makes sporting a 140 horsepower rating, 
or 28 horses per hole.  But the 1.9L kept its 90 horse rating instead of 
graduating to the expected 28 times 4, or approximately 112 horses.  
Well, I just learned that in May 1996, the new 110 horsepower rated 1.9L 
TDI was released for sale to German buyers, so the disparity is gone.  
Ordinarily, this kind of develpoment is followed in their other markets. 
"Look mom, it's a four; 110 exceptionally strong diesel horsepower 
transplanted into a Vanagon without raising the rear floor 7 cm."  Or was 
that a tooth paste ad? :)  I'd expect one of these would run away from a 
100 horse 5 cylinder Audi transplant because of their different 
respective torque curves.
  I'd mentioned what I believe to be a fact about how "strong" individual 
motors feel in normal day to day street driving.  This fact is hard to 
articulate, but can be described as follows: the average torque developed 
between the rpm shift points that drivers actually find comfortable 
using, dominates in determining drivers' perception of that motor's 
in-service strength rather than its peak horespower rating which 
only occurs at one rpm (and too often sounds and "feels" like motor-life 
shortening abuse in many gas motors).  I further commented that in the 
case of these new Audi/VW direct injection TDI motors, with their torque 
peaks occuring around 1900 rpm, street performance comparisons between 
equally high peak-horsepower rated gas motors and TDI motors consistently 
favor the TDIs because they deliver stronger average torque between their 
respective normal shift points.  With that in mind, consider this quote 
is from a person who tested the TDI sedans in Germany.  "Passing in the 
90 HP TDI is about the same as the 115 HP 2.0L gas, but with amazing 
economy."  I attribute this strength comparison to their very different 
torque curves.  The TDI's powerful bottom end torque is MUCH better 
suited to propelling something heavy like a 4900 pound Westie.

  To take a peek at the new VW Sharan van model with photos and some 
technical data, try the following site:  http://www.vw-audi.co.at/
It's german text, but you'll easily read their technical data charts.  If 
someone doesn't get to it before me, I'll eventually convert and repost 
their measurement units to those more typically recognized by US readers. 
Please pitch in as I'm swimming in information overload, and have too 
many interests.

  John Wakefield