found this letter/answer in the June 1996 issue of Road & Track, in the
section Technical Correspondence, edited by Douglas Kott:

Bag the boxer?

I'd like to put a larger engine into my 1987 Volkswagen Vanagon Syncro that
currently has the stock 2.1-liter boxer motor, which is very underpowered
for highway hauling.

Do you know if any conversions to V-6 power or any other type of engine
(excluding Porsche) have been done? If so, could you put me in touch with
the individual or company that has done so.
                          Tom Fitzpatrick
                          Okotoks, Albert, Canada

and their reply:

It's a shame that your rather specialized water-cooled flat-4 is not as
easily modified as the earlier air-cooled VW engines, where an entire
industry has been created that manufactures stroker cranks, big-bore
cylinders, high-flow heads, etc. Scanning the ads in a recent copy of
Dune Buggies and Hot VWs turned up two firms that sell stock rebuilt
Vanagon engines, but they don't offer hotted-up engines.

Unfortunately, the most popular Vanagon engine swap does involve the
Porsche flat-6 engine and is carried out mostly by tuning firms in
Germany. As you probably know, such conversions cost at least as much as
your entire Vanagon.

We have heard that some people have converted the early Vanagon diesel over
to gasoline power. Evidently Volkswagen's water-cooled 4-cylinder from the
Golf bolts right in and makes the Vanagon far more hospitable to own and
operate.

But for your Syncro, perhaps you could contact a race-car fabrication shop
that has experience with Volkswagens. For the right sum, they might be
interested in doing a one-off conversion.
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