"Jay Honeck" wrote in message
news:KrVCd.620164$wV.262033@attbi_s54...
I've used mogas for so many years I've forgotten when I started. Use
the supreme and you should have no problems. I don't know the tech
reasons or the difference in heat generated on the valves, but as a
precautionary measure, I kept the mixture just a little on the rich
side for power applications. Never had a single problem that could be
attributed to the use of mogas. Used it in both low horsepower, and up
to the 300hp in ag aircraft.
I HAVE heard of guys who tried to go the cheap gas route and had
premature engine failures or overhauls with valve problems. In the long
run they ended up paying a lot more for their pecuniary efforts.

Using premium car gas (92 octane or higher) is completely unnecessary, if
you've got the STC.

Our old engines were designed to run perfectly on 80 octane fuel. 87 -
89 octane regular unleaded car gas is perfect for them.
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I've never really had any dealings with an mogas STC. Do they acctually do
anything to your engine or do they just change the stickers.