>I saw my first VW industrial engine this weekend.  It was from the early
>'70s and had a crank-start pulley bolt.  Cool!  Other interesting features
>were the magneto (Genuine VW made by vertex in switzerland) , the fanshroud
>(no ports for the heater tubes and neat "Volkswagen Industrial Engines"
>sticker) and the exhaust (two two-into-one pipes that exited straight up
>into the area normally occupied by dual carbs--looked stock)
>
>Anyone got more info on these?

VW engines were often put into small homebuilt aircraft, usually
single-seaters. Most basic conversion for aircraft use, included
removing the fan shroud, replacing the crank pulley with a hub to
hold the propellor, putting on a different carb and manifold... and
replacing the distributor with that Vertex magneto.

Advantage: mag was more reliable. Disadvantage: No spark advance, so
the idle was real rough. Also, the engine turned faster than a normal
aircraft engine, which normally put out max power at 2800 rpm or less.

Many companies sprang up in the '70s to do professional conversions
of VW engines for aircraft use, and they put a lot more work into them
than these minor mods. Expensive, but worth it-- when an aircraft engine
fails, you can't just pull over and park.