yes this is the distilled version of what is in the archives.  thanks for
putting it out there mark.  i was skeptical to say it myself as i have
never tried it.  thats why i was pointing at the archives.

jonathan

On Fri, 16 Apr 2004, mark drillock wrote:

> I have tried it and you are right to be skeptical. VW knew what they
> were doing. The DK tranny gearing is to tall for a diesel Westy with
> it's stock 1.6 engine. This is because of the power to weight ratio of
> the vehicle along with the aerodynamic drag.
>
> The problem is not just that 4th gear is too tall but that the spacing
> between the gears is too great for the powerband of the engine. You
> can't easily get going fast enough in 3rd to make the jump to 4th unless
> you have a tail wind or slight downhill. When you do shift to 4th the
> vehicle won't pick up much speed until you have the advantage of the
> wind or a slight downhill.
>
> VW solved this problem by using 5 speeds starting with 1983 diesel
> Vanagons. These have a top gear similar to gasoline models but a close
> ratio between 2-3-4-5 allows you to drop back a gear without reducing
> your speed so much and you don't have to wind out every gear before to
> shift up to the next one.
>
> I did once have a passenger model diesel Vanagon with the aircooled DK
> tranny and it was nice to drive. The engine was from a later model
> diesel Jetta that had been tweaked for a little more power and it pulled
> the empty vehicle just fine with the DK. Much nicer on the highway
> without the engine screaming for mercy at high rpm all the time. Put 4
> people in it or some heavy load and it bogged down to the point that it
> was hard to get it or keep it in 4th. As long as it was not loaded too
> heavy it was more enjoyable to drive with the DK.
>
> Mark
>
> Tobin Copley wrote:
> >
> > I'm skeptical about that last assertion.  As a regular (summertime)
> > driver of my diesel westy with a stock diesel transmission and stock
> > 1.6L NA motor (48 HP on a good day), I can't imagine wanting any taller
> > gearing than what the stock transmission provides.  I live in a
> > mountainous region, where when I'm loaded in camping trim even a mild
> > uphill grade knocks me out of 4th gear down to 37 mph in 3rd, and on
> > the steeper grades (say, over 9% or 10%) down to 22 mph in 2nd.  If I
> > want to go faster than 60 mph downhill, I put the clutch in.  :-)
> >
> > Or maybe I'm missing something.  *How* (or perhaps under what
> > conditions?) is the aircooled tranny better than the diesel
> > transmission for the motor the diesel tranny was designed for?  *Maybe*
> > if I lived someplace flat, windless, and drove empty all the time I
> > could understand upping the gearing a bit, but from where I sit, it
> > doesn't look like an attractive option.  Can you shed some light on
> > this?
> >
> > T.
> >
> > On Apr 16, 2004, at 2:19 AM, Jonathan Farrugia wrote:
> >
> > > the exchange in the archives is not about using the air cooled
> > > transmission for engine swaps or upgrades, although that does exist.
> > > it
> > > is about using a air cooled transmission coupled to a 1.6 normally
> > > aspirated diesel engine.  the air cooled transmission can
> > > satisfactorily
> > > be used as a direct replacement for the original diesel transmission.
> > > some in the debate even say it is better suited to the diesel engine
> > > (1.6
> > > normally aspirated) than the original diesel transmission.
> > >
> > > jonathan
> > >
> > >
>