[daepp]

Is their a link here? I know Mooney used a Porsche engine on a limited basis, but that's not what I'm talking about.

These engines are all too similar to not be related somehow. Flat opposed, split case, etc. Did they all license from Porsche?

Anyone know which evolved first? Wasn't Porsche using its flat engines while the aircraft industry was still using radials and in-lines?