"David E. Powell" wrote in message
...
I bet the Honda Civics and some of the Subarus have some pretty neat
light engines in them.

The past decade or two's "rice rocket" obsession in car customizing
should have some neat impact on light, powerful engines and parts
available to the airplane homebuilder.

Keep in mind that most of those super hot little engines are run at full
power for applications similar to drag racing. Presuming that they can
"last" that way, 50 hours is likely to be a very old engine.

Just so you know, I was a long time advocate of automotive conversions and I
really do still like a lot of them; but, like so many of us, I am getting
old--to the point that, if I do finally get to build, I am likely to chose
something like an RV-9 and a Lycoming O-235. The problem is that there are
a couple of old rules of thumb--that still seem to work pretty well--and the
RV-9 has replaced the Tailwind, the Vari-EZ, and a couple of others as the
established design that comes closest to meeting or beating the probable
performance and efficiency of everything on my personal scratch pad.

Now, admittedly, there are still a few designs on that scratch pad that are
a lot faster--and a few that would probably be more fun including feeding my
personal pride--but I still have to admit to myself that "dispatch
reliability" is a very real component of both performance and efficiency,
and I also know that those old type certified "dynosaur" engines can run as
lean as you please below about 60 percent power--and the RV-9 have very good
published numbers at 55 percent. When you want to really cover the
distance, for those few long trips per year, you just rev it up and pour on
the fuel. Still not super fast; but fast enough to be a seroius contender!

That's just the real world as I see it.
Peter