I want to build one for my wife

That thing gives me the willies! I wouldn't let my mother-in-law fly such an engine. You could use nickies to lose the weight and keep four cylinders, or better yet run a BMW R100 air-cooled engine. (Not the oil-head).

How 'bout a radial 6-cylinder 'VW' cylinder engine? Here:

thing, that.

Ya know that Frederick Porsche first positied a radial engine for the Bug?

The mods to make a 2 cylinder VW are nutts. A company in Ohio called Hummel make turn-key 1/2 VW engines. Here's a shot of one:

I like the way the useless back half is chopped off.

LN does make fully round finned cylinders for the 1/2 VW guys. To me, the mods to the stock heads seem silly when a pair of scat split-ports would seem perfect as is, except that the intake manifold is coming from the top. There's a requirement that the carbs be located in such a way that they can't drip on metal parts of the engine.

Perfect! I agree. Power for the prop would need to come out the front... Turn the engine around? That might work.

That's psycho. Much too heavy for an ultra light. Very pretty. 1.9" stroke? That's super short.. why so short?

I love google:

Why do people tend to chop the engines in half when building aircrafts? Why not use the whole engine? is there a reason for this?

BTW, Who's "Frederic"?

Karls

Okay, Ferdinand.

Weight and speed, thus power, restrictions I think. That legal eagle plane only needs 40 horsepower.

"a powered vehicle must weigh less than 254 pounds; is limited to 5 U.S. gallons of fuel; must have a maximum speed of not more than 55 knots;"

Found some more pics for it. Very cool, but it seems to have never gone into real production.

VW engines for airplanes run under whole different set of requirements. I'm learning new stuff. Like how important it is to keep the exhaust valve area well cooled (air flow is now from the back rather than from the top) and that best prop rpms isn't best engine rpms and how horsepower is essentially meaningless.

I recall someone saying that 12.5 HP where needed to maintain 65 mph in a bug. For an airplane on accent, much more continuous HP is required for longer periods than one would use for a car... hmm.. Interesting stuff.

It seems plane guys use a dual plug setup in case one fails. And I found info on the glow-plug catalytic "spark plug".

Running an engine on a stand with a prop is a built-in load so rpms essentially equal power output..

Just thought I'd share..

Yep, the very strange distant location of the carb on the 4-cylinder is a good clue to what you said earlier - the carbs can't drip on the engine. Civilian aircraft engines are largely about reliability and torque. Long stroke, lazy, reliable engines. Dual-plugs, dual coils per cylinder

*gasp*. All that. It's a whole different world where when the engine stops you can't just pull over to the side.

What bugs the hell out of me is the 5 gallon restriction on experimental aircraft. We had one of them crash into town here on his way to to the Wisconsin fly-in. He ran out of fuel and died coming over the 600' bluffs in an otherwise plain terrain. 5 gallons. WTF is that all about?

Probably a desire by the FAA to restrict the range of such planes.

Not range, but fire/explosion hazard in case of a crash.

Karls