Regarding intercooler in a Jetta or car compared to a bus.
In my opinion the intercooler is very desirable in a TD van
because the small Diesel in the van runs on average at
twice the load of a car application. In this case the intercooler
supplements the regular cooling system and keeps egts at
lower levels.

The 1.6 and 1.9l TD's were designed to not run under or near full
boost in the cars during most normal driving. In a car the intercooler
is only active during accelerations or long steep uphills, and
then lets you increase fueling for more power.

Hence in the bus the advantage is twofold: both longer engine life
due to lower thermal loads, and with increased fueling more power.
In a car the effect on engine life is likely small, but you still
can get more peak power.

/Martin
--
Westy 1.9l Turbo Diesel
Quantum 1.6l Turbo Diesel

New and used parts for sale, gas and Diesel:

    http://www.cs.yale.edu/~jag/vw/forsale.html

Martin Jagersand                 email: jagersand@cs.jhu.edu
Vision & Robotics lab, CS Dept          jag@cs.yale.edu
Johns Hopkins University         WWW:   www.cs.jhu.edu/~jager

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