sopwith

I have been running all of my glow engines on E85 for about 3 months now. The cost of Methanol became too high for my thin wallet. E85 is a poor fuel compaired to methanol, but for a sport pilot who doesn't need the full power of methanol+nitro it is managable.
For successfull operation you need to use a very cold plug or a good 4 stroke plug. The ideal would be a cold 4 stroke plug. Remember that a hot plug means less platinum and a cold plug means more. The catalytic effects of ethanol are les than methanol so you need more platinum. Also the 15 to 30 % gasoline added (in Colorado they add up to 30% gas in the winter to help starting) adversly effects starting and general running for a glow engine. I found that a Duratrax gold plug or a thunderbolt 4 stroke plug (#115490) work well and don't stress my thin wallet. The Fireball brand and Fox brand plugs work very poorly. An OS R5 cold plug is not as good as the Duratrax gold and costs more. Cold starting (sub freezing) is very difficult, using a prime of pure methanol helps alot. The power output is much less than when using methanol without nitro (nitro is too rich for my thin wallet, so I never use it), typically 500 to 1000 rpms less, but run times are almost doubled. I also use only 10 perecnt oil, and can use a smaller fuel tank to save weight. I only use synthetic oil, as caster becomes like glue in my engines in cold weather (I store all my flying stuff in an unheated shed). I use 13 ounces of Morgan fuels green heavy Kart oil per gallon. It is cheaper than caster oil and I have never had a problem with engine damage (I used the same mix when I used methanol as the fuel). In the hot summers I add 5% water for cooling when using methanol, but since I have only been using E85 this winter have not tried it with the E85. Glow plug sensitivity is severe with the E85 in most engines. I have some OS FP .25 engines that run fine even using a standard OS8 plug, but everything else requires 4 stroke or cool plugs. Using an older engine designed for little or no nitro seems the best bet. I would be interested in hearing the results of others using engines different than mine. I have super tigre .45 engines, and they run poorly on E85, the OS FP .25 runs well, but the .40 not so good. I have a thunder tigre .45 that runs nicely, having better needle valve operation, but those are the only engines I currently have. I want to buy some .60 engines to get some more power for my .40 planes now that I use E85 and would love to hear how each brand runs before stressing my ever thin wallet.
The E85 costs about half of what pure methanol costs here, so I intend to stick with it until I have solutions to all the problems. Another good thing about E85 is it's lack of toxidity compaired to methanol. I have the 30% gasoline version of E85 now, I hope the 15% summer blend solves some of the problems in a few months.