My 8A specifies 100LL in the POH and on the tank fillers, but I would like to start experimenting with a mogas mix (initially 25%, then 50% and possibly up to 75% eventually) for cruise. Cost is a secondary consideration - my goal is to reduce the potential lead deposits in the cylinders, plugs, and oil. UL94 is not readily available locally, but non-ethanol gasoline is. I operate at high density altitude and don't anticipate any trouble with knock, although it is comforting to think that even a small proportion of 100LL confers a significant vapor pressure and antiknock benefit.
What do I have to do to "legally" change the plane to allow the use of other fuels? Does this require an engine logbook entry?
What do I have to do to "legally" change the plane to allow the use of other fuels? Does this require an engine logbook entry?