" jls" wrote in message ...
Let's say you mix 1 part avgas with 3 parts mogas for use in your flying
O-300-powered demon. You have an STC for doing this, of course.

These two fuels have different specific gravities, so it is said. Do they
stratify? I don't believe they do. Anybody have a comment? I guess you
could pour samples into a glass tube and watch and see if they get it on or
avoid each other.

They would only stratify if they didn't dissolve in each other. Probably 90%
of the gas is the same hydrocarbons so you're not going to be able to separate
out one from another.

Mixing mogas and avgas is approved by both the EAA and Petersen STCs.