G.R. Patterson III wrote:

Petersen has an STC for the Skyhawk with the O-320-D2G.
http://www.autofuelstc.com/autofuels...nAviation.html

So they do! Thanks for the pointer. Interesting reading--no ethanol
blends are allowed, and the STC for the D2G engine requires a minimum 91
octane rating. Reading the descriptions of airframes/engines that failed
certification tests due to "failed the vapor lock test" causes some
concern, particularly for the high altitudes I must often fly at.

Since self-serve 100LL is only $2.45 at my home base, the cost savings
of using premium mogas in a Skyhawk would be minimal. But it's nice to
know a simple STC is available in case the unthinkable happens--sources
of 100 octane avgas drying up.

N.B. there are LOTS of engine/airframe combinations mentioned on the web
site.

Jim Rosinski
N3825Q