That's a commendable piece of work there and it's all in the name of progress and enjoyment to experiment and find a working alternative, but at that given price for the fuel required I should think that going gas/ignition would be a more attractive and cost effective way in the long term.

Karol

Ed, does this work mainly with 2-strokes? I have mostly 4 strokes in my fleet and would love to convert them to gas but without having to add the weight of ignition. I do have a ST S75 that I think I will try your mixture with. Here's a question, seeing how the ethanol in gas is bad for our little motors. What about using Coleman white fuel? It seems to be a growing trend as it is 100% unleaded fuel. It is a little more expensive than pump gas, yet less than half the price of nitro. [link]http://www.idealtruevalue.com/servlet/the-45832/Detail[/link]

Shane

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E85 was $1.67 a few weeks ago in a small town named Dalton here in GA a few weeks ago.

I haven't priced the Klotz oil that Greg recommends for use with E85 as yet, but how expensive can it be?

Addressing another poster's comments about ignition system weight, as far as the weight of the ignition system goes, it will be negligible in my Great Planes Ultimate Biplane 1.60. The OS 1.60FX should really turn into a fuel miser with that setup, since it is already really good on fuel consumption as a glow engine. That and being able to use the stock OS carb with the ethanol/gasoline mix makes it sound like a real winner.


Ed Cregger

Coleman fuel is just high grade, no impurities unleaded. If you are going the ignition route and running gas it probably is the way to go for quality, ease and smell. I don't want to sacrifice any weight. Therefore use glow engines with no ignition on the E85 type fuel. About 300 rpm performance loss is all and the cost per gallon with oil is $7.00 or less. With the correct tuning and the right plug I see no kneed for ignigition and battery weight. The dedicated gassers are also heavy for the power they produce. Whe you see the idle speeds and transitions of the big Tigres and Moki's I have it will convince you that ignitions are not needed with this set up.

I am working on a video, but don't want to publish it until the spreadsheets of data are all done to show the supporting info to the actual video. The oil mixtures, etc. are based on temperature of 15% nitro Cool Power fuel and used the right amount of oil to match those temperatures and protection. When I'm satified with the numbers being accurate and the video is finished as well I will publish it here in this thread.

Motors I will be using in the test range from: S2000 Super Tigre, 1.8 Moki, 1.00 NX Evolution, S-90K Super Tigre, FP40 O.S. Max, FP25 O.S. MAX, Saito 150 to name a few. I will run them on 18-20% oil mixture depending on the motor. O.S. F glow plug. Will take head and exhaust temperatures with the Cool Power and the E85 and use tach readings with various props. If anyone can think of something else they want to see in this testing by all means ask and if it is worth doing I will include them.

Eric

It should work equally well with four-strokes in addition to two-strokes. The octane rating of the ethanol/gasoline combo should be high enough not to cause preignition problems.

I favor the spark ignition system because it permits one to tune the mixture much leaner, without worrying about advancing the timing too much, as with a glow plug. The leaner mixture also reduces the amount of oil expelled by the engine.

Power output will be down slightly from methanol and oil only, but you recover a tad bit of that by running a leaner mixture with the ethanol/gasoline combo, minus the boost of nitromethane you might have used in conventional fuel. Those desiring top performance will not be interested in this approach. Those happy with a little less power at a big savings in fuel cost will be shickled titless.


Ed Cregger

If you don't want to sacrifice power put 1 part 15-30% nitro fuel to this E85 mix and you get the pop you want for more performance. So you are running this E85 blend 2 parts and one part nitro fuel. Still a big cost savings and yet have some performance. This works well in the cold times of the year as well. Like we are having here in Ohio right now. 7F with -5 windchill.

Great Ed, thanks for the info. Looking forward to your reports.

Shane

Me too!

Now to get busy again selling off a ton of ARFs I have collected while my legs were healing (took several years). Once I get my shop back, in a few months hopefully, I can get back to modeling real time again. Still have a new mill/lathe combo to unpack and set up. Nothing expensive, but good enough to make the crankcase collar I will need to position the ignition system's Hall Effect transducer. After that it should be a piece of cake.

If this works out in the fashion I think it will, I may begin looking around for a Super Tigre 4500 or the huge OS 35cc glow engine for conversion to E85. I'll try it with the ethanol glow plug as the other poster suggested, just for hoots. I want to be able to document the difference between both glow and ignition system operation. I'll bet that Greg beats all of us to it. If not, Hobbsy probably will.


Ed Cregger

A gallon of super technoplate is $63.60 shipped. That's $12.60 per gallon of fuel mixed at 20%. Add in the cost for E85 and it's over $14.00 a gallon. Will need to use a gas stopper and can't use sullivan flex tanks or silicone fuel tubing.

When I purchase my fuel, I order 8 cases at a time from my LHS and get 5% nitro 20% oil Byron fuel for less, shipped! Good fuel and performance.

I don't know where you are getting your oil, but you got screwed.

Rats! May as well not bother.


Ed Cregger

That's the price direct from Klotz. I paid $34.00 plus shipping for my gallon five years ago. Use it to increase the oil content for mehanite engines.

Where do you get yours, oh great one?

To me,

The advantage of gas is using less oil. The best synthetic oils compatible with gas are $12.00 a quart but you only need 1/2 pint per gallon for most engines. Pennzoil pricing is less than half that. This way gas is still cheaper than glow even if gas goes up to $6.00 a gallon.

When using a spark ignition system, you can lean out the mixture without advancing the timing, unlike when using a glow plug. The result is better fuel consumption if the engine is tuned properly lean.

Unfortunately, we are still going to have to use 15% lube (or more) by volume when burning alcohol/gas mixture in our plain bearing connecting rod and ball bearing equipped engines (OS 1.60FX). That will drive the price of the fuel up quite a bit, but might still be worth it in the long run.

Of course, we're back to making a mess on the model again with the high oil content, as with glow fuel, but what the hey...


Ed Cregger