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Gerry | Vanagon
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Subject:Re: TDI Eurovan
Date:Tue, 4 Jun 1996 12:28:21 -0400

In a message dated 96-06-04 10:40:11 EDT, you write:

>  Here's a point for someone to clarify for me,  as I understand
>(having driven a heavy truck (18 wheeler, realy a 22 wheeler, but whose
>counting) and owned several diesel autos and light trucks).  All diesels are
>direct injection,  the fuel is injected into the individual cylinders by a
>single (noisey) injector located roughly where a spark plug would be placed
>(1 per cylinder) if the engine were gasoline powered.  My point is this,
>what does direct injection mean?  Quite bluntly, I think that it is nothing
>but add-hype.

No. All diesels are not direct injection.  This is a new technology that VW &
Mercedes have pioneered.  In a traditional diesel the fuel is injected into a
pre-combustion chamber in the head connected to the cylinder itself.  The
shape and position of the pre-combustion chamber has something to do with
properly starting and controlling the diesel's combustion flame front but is
innefficient.  The new technology of being able to inject diesel fuel
directly into the cylinder is new and much more efficient.  Notice how much
more horsepower they're able to get out of a TDI engine?  I think the old
1.6L turbo-diesel in the Jetta & Quantum made 68HP if I remember and I think
the new 1.9L Turbo-diesel Direct Injection engine makes 90HP.  Thats a 32% HP
improvement with a 19% increase in displacement.  The TDI is also quieter and
less poluting.

Jim Davis
87 GL Syncro
88 GL Wolfsburg