Re: 4000 Quattro Turbo

[ti@bazooka.amb.org (Ti Kan)]

>I just talked to my mechanic about turbo-charging my 4000 Quattro.  He said
>that there isn't enough room in the engine bay to use the Audi 5000's turbo.
>He said that the 5000 has a couple more inches between the frame rails and
>the fromt struts are farther back from the engine.  The turbo would be right
>were the front (right?) strut is.
>
>What about the 4000 based Coupe Quattro?  Where is its turbo located?
>Could some of its parts be used to locate a turbo in the 4000?

The quattro turbo Coupe uses a different exhaust manifold and other
plumping arrangements than the 5000 Turbo.  

A few words of advice...  Fitting the turbocharger is going to be the easy
part in such a conversion.  The factory 5-cylinder turbo engine is itself
different from the normally-aspirated version.  First, the bottom end is
different: the pistons are different for lower compression, the connecting
rods are different (stronger), and the block is equipped with oil jets
that sprays the bottoms of the pistons for extra cooling.  The head is
different as well: the camshaft has a milder profile to fit the turbo
engine application, and the exhaust valves are sodium-filled.  The
ancillaries around the engine are different as well: The intake manifold,
throttle valve and associated intake plumbing are completely different,
the oil system has extra oil coolers and additional oil filter, the
radiator and cooling system has an extra electric pump that circulates
coolant through the turbo after shut-off, the fuel injection and
electronic ignition computers and wiring are _very_ different, not to
mention the myriad of sensors.  The turbo models have the battery under
the back seat to make space for the waste gate, with a big electrical
tap in the engine compartment for jump-start purposes.

Even if you get an entire Audi turbo engine you will still need to A LOT
of custom fabrication to get everything to fit.

I can go on and talk about the suspension, brakes, transmission...

The point of all this, is that a lot goes into producing a smooth-running
and reliable turbocharged car.  Simply bolting on a turbo without all
the other enhancements will surely be a disaster.  If you really want
to go ahead and do the conversion and add all the enhancements, the
cost would be so prohibitive that you might as well go and buy a
turbocharged Audi.

This is not to say that you shouldn't do this.  I know of people who
have done just that, and the results are stunning.  But you should
think it through and be aware of just what you are getting into (and
how much of a money sink this is going to be) before you're in it deep.
The guy that I know who converted a 4000 quattro into a "4-door quattro
turbo coupe" spent well over $50,000 (yes, that's fifty grand) when
it's all said and done.  The car would surely not even approach that
in resale value.

If you really must have a turbo, an alternative to using all factory
parts is to locate the Callaway Turbo kit for the 4000 quattro.  As you
might know, Callaway is no longer producing this kit, but there may
be one available somewhere.  It wouldn't hurt to do a little investigative
work and make a few phone calls here and there.  The Callaway kit increased
the horsepower of the stock engine to over 170hp.  This is more than the
factory U.S.-spec Audi 10V turbo, but it is not likely to have the same
longevity as a factory turbo engine.

Whatever you decide to do, the best of luck to you, and please share your
experiences with the net...

-Ti
--
    ///  Ti Kan                vorsprung durch technik
   ///   AMB Research Laboratories, Sunnyvale, CA. USA
  ///    ti@amb.org
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