Comment

Comment by Bob Pustell on September 11, 2015 at 12:56pm

I am not yet a Corvair flyer, just a wannabe. The plane and engine are far from complete. However -- As far as mixing fuel goes, a little bit of Tetra Ethyl Lead in fuel brings the octane rating up quite a ways. Supposedly mixing 100LL in a one to four ratio with automotive regular brings the blend up well into the ninetys, octane-wise. It also has the virtue of decreaseing the amount of lead per gallon in the resulting fuel, a good thing for almost any engine. The only thing 100LL is low in lead to, comparison wise, is the old no longer available 130 octane Avgas. It has more lead than 80 or 91 octane avgas had and also more than pretty much any automotive fuel back in the days when Mogas had lead in it.

You do need to be careful of the ethanol in most modern Mogas. Ethanol is totally illegal in certified aircraft. In your homebuilt you have the right to experiment with Ethanol contaminated fuel but be sure to educate yourself on all the problems before doing so. I am lucky enough to have 91 octane ethanol free available in my area, plan to mix some 100LL with that for my Corvair when the time comes.

Comment by Dave Gardea on September 5, 2015 at 2:46pm

Hi Robert, good article entitled Compression Ratios, Fuels and Power Output just recently published on William Wynne's blog at Flycovair.net. Good read on fuel choices. Regards, Dave