I don't want to muddy the water to much, but there is a small movement to spark ignition using methanol (glow fuel). Much better economy, about 20+%, and a much easier handling engine. You can use FAI fuel and still have more power than an equivalent gasoline motor. From what I hear, oil content can also be reduced somewhat.

I was able to hold in my had an Evolution 10cc gasser last week. It looked identical on the outside to the glow version. The CDI box is compact and it's an ABC design motor. Personally I prefer a ringed engine, but that is me and nothing against the Evolution. So far all the user reviews that I have read, don't have anything bad to say about it. It sounds like as more experience is gained with the motor there may be a reduction in oil usage (mix ratio).

Ken

My next sport plane will be 70" or bigger. Gas it will be. About the only thing I buy from the local hobby shop is nitro fuel. Just that trip to the LHS is a gallon of gas. The long term cost advantage over both nitro and electric is huge if you fly a lot (I do at least 20 flights a week).

I'm stating my 5th gas plane and have never used a separate ignition battery. Smallest plane is 72" WS with a 17cc engine.

Gas is now practical down to a .46 size plane with the advent of the Evolution 10GX. I flew mine 18 times in January for a fuel cost of about $3. Glow would have cost $25.

Practical to me also includes things like performance, reliability, ease of starting, and ease of clean up and all those things get good marks with the 10GX.

Though the jury is yet out as to long term issues, after eighteen flights... I'm happy and impressed.

Originally Posted by AA5BY

Gas is now practical down to a .46 size plane with the advent of the Evolution 10GX. I flew mine 18 times in January for a fuel cost of about $3. Glow would have cost $25.

Practical to me also includes things like performance, reliability, ease of starting, and ease of clean up and all those things get good marks with the 10GX.

Though the jury is yet out as to long term issues, after eighteen flights... I'm happy and impressed.

Great post AA5BY!!

I used to use the rule of thumb that if it was a 1.20 size or larger plane it recieved a gas engine, period! Now I own 2 of the Evolution 10GX's and they are awsome. I also have a DLE20 and a DLE30, DLE55 2ea, DA50, DA100 2ea, Quadra 50, RCGF 50, SV Hobby 50 twin and a zenhoa G26. I also have a Dove Jett .40 that I hope to try out today and a couple of othe rsmall glow engines that do not get much runtime anymore.

I like gas because there is no way I am putting a glow engine in a 35% or 33% plane

So for me it is gas, all the way down to the 40 size planes.

Originally Posted by rjstrickjr

I like gas because there is no way I am putting a glow engine in a 35% or 33% plane.

Definitely don't want to have to pay for that!

I had a 1/3 scale Spacewalker with a DL50, I just sold it last fall. On glow it would have only gotten a few flights a year! The only problem I had with it was vibration which it had big time. Kept breaking the tail brace wires from all the vibration. Now I'm back to all electric.

Mike

There's a device that Troy Built sells called an IBEF (ignition battery elimination filter.) I have one but haven't used it yet. It has a filter to eliminate the possible electronic noise from the ignition and an electronic switch for cutting the power to the ignition to kill the engine and runs your ignition by drawing power through the receiver. I haven't heard of anyone having problems with them and can save the extra battery weight in smaller planes.

Mike

Originally Posted by Smash McCrash

There's a device that Troy Built sells called an IBEF (ignition battery elimination filter.) I have one but haven't used it yet. It has a filter to eliminate the possible electronic noise from the ignition and an electronic switch for cutting the power to the ignition to kill the engine and runs your ignition by drawing power through the receiver. I haven't heard of anyone having problems with them and can save the extra battery weight in smaller planes.

Mike

I have an IBEF also. I've tuned the engine but haven't flown it yet. Seems to work ok, I did a range check with a telemetry module and didn't have any fades or loss's on the radio. It lets you regulate the voltage to the ignition and also a cutoff switch from the transmitter. I got the one that has the regulator, IBEF and 2 batteries. I would have flown it last weekend but it was too windy

Originally Posted by rjstrickjr

:

I like gas because there is no way I am putting a glow engine in a 35% or 33% plane

.

There was a moment where I was sizing up a Moki 2.10 on the plans for my current project, a Ziroli Beech D-18. I canned that idea and ordered two G-38s instead...


For me, I have so many glow engines that the cost of fuel is a moot point as I would have to balance the cost of the engine as well. Kind of like the old saying - the cheapest car is the one you already own. The larger European glow engines are high enough compression to run very well on 0% fuel, so the cost savings is even less as you can mix your own FAI fuel for around $8/gallon.

I did purchase an Evo 10GX and will be running it this spring. Still am undecided on the airframe....

Has anyone used a FG-21? I want one but have heard the 4 stroke gassers don't do as well.

Redundancy is the key here not only do I use separate battery for ignition but I use 2 batteries for the system through a smart fly board or a batt share. Plus an optic kill switch

I just looked at the evo 10 gas, they are only $200. Considering that a Os 60, witch is about equivelent, is around $150. I would say that gas would be the way to go if I were to buy a new engine.

Originally Posted by cloud_9

Thanks guys. Gene, my thinking from the reading I've done is that you have an extra battery with gas that adds weight. Also gas has less power per displacement, or per engine weight, so you have to put in a heavier motor for the same power.

Thus, the extra weight is going to be a problem unless you are into a big plane. You examples of small gas motors makes me thing my impressions may not be right?

Jim

Not so My DLE 30 gasser will blow away any 180 glow out there.
The only glow close is the moki 210 and thats a bigger motor

Originally Posted by kerwin50

Not so My DLE 30 gasser will blow away any 180 glow out there.
The only glow close is the moki 210 and thats a bigger motor

Are those 180 glow engines 4 stroke? That would make a difference. Does anyone make a 180 2S glow?

Super Tigre and ASP both make a 180 2 stroke