I came across an interesting set of slides that go into considerable
technical detail about the problems of coming up with a replacement
for 100LL. The conclusion: Avgas 91/96UL (Unleaded), as apparently now
available in Sweden. Check it out:http://www.iaopa.org/info/assembly21...iles/frame.htm

We have used unleaded regular car gas in our plane(s) since 1998.
Since 2002 we've run over 9000 gallons, without a hiccup. The price
difference between mogas and avgas has paid for our fuel truck, the
tank, and most of my next engine overhaul. Best of all, the plane
runs *better* on it.

Of course, you need a low(er) compression engine to use mogas, which
does present a problem for many aircraft owners. High compression,
fuel injected engines generally need the higher-octane stuff -- so
perhaps this "Swedish blend" will help owners of those aircraft out?
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"