Sokat

Hi fellow flyers.
I have been reading about this conversations specifically beet and David from glow to gas with spark ignition
I am thinking of converting my fa100 I got it with model. I spoke to mmm and he told me you don't need to change or modify glow carb. It will just work fine.
I just want some input if anyone done this. Also if I just use glow fuel would it run better with less nitro and leane saving some fuel.
Thanks for your help.
Sokat.

1967brutus

I hate to say it, but MMM is full of crap when they say "it will work just fine".

It won't...

Sure, it will 100% sure RUN, it will be "throttleable" and it will even be fairly reliable.

It will run, but it will basically only run "clean" at idle and at full throttle. Anything inbetween it will hog and sputter, and it will hog and sputter REAL BAD.
It will be throttleable, in the sense that if you reduce throttle, RPM goes down, eventually, and if you increase throttle, RPM will go up, eventually. But it will not be immediate, it will not be consistent and it will not be precise. Try landing a plane with an engine not consistently responding to subtle throttle changes...
It will most likely be reliable. That is the only thing.

Further the engine will with near 100% certainty barf out large amounts of black crud.

And if I may be so blunt: Do not trust MMM's conversion kit including a special gasoline carb either. They are beautifully made, but the carb selection is a hit-or-miss affair. I have re-done a few of their conversions.

MMM has hundreds of videos on their site. But try find video's of happy customers actually flying their MMM converted engines.

If you are out to save a bit of methanol fuel, and run without Nitro, then the MMM kit is a beautifully made spark conversion and will work allright.
Because there is nothing wrong with the material quality of what MMM supplies.
On spark ignition, a stock methanol carb might have a tendency to a slightly rich midrange, but usually that will be well within acceptable limits.

Sokat

Until I get solonoid and control valve to convert my saito 100 to gas I will use nitro with spark. I can get cdi from Ali express just need sensor ring or drill in the magnet.
Anyone point me to the right direction for sensor ring as mmm ring bit pricey.
Thanks

1967brutus

I typically drill a 3 mm hole in the propdriver, and glue in a 3 mm dia, 6 mm length magnet in the driver.

mind you, for methanol, you will need a timing of 32~34 degrees BTDC, for gasoline that angle is 27~28 degrees.

Sokat

So I have to get ring or theagnet want be adjustable. And I can't frill 2 holes. Damm

1967brutus

Not necessarily, you can also make the sensor bracket adjustable. Has the same effect.
You can drill 2 holes if you want: they would be roughly 180 degrees apart, and you would need to glue in two magnets of opposed polarity. The sensor is polarity sensitive, and by turning the sensor you can determine which magnet it responds to.
For example, drill the holes such that the magnets are sideways to the left and right when the piston is in TDC.
Make a bracket on the right side adjusted for the one angle, and a bracket on the left for the other angle, and relocate the sensor as needed.

That is not the only way...

I have seen people make magnet holders from thick walled aluminium pipe of a suitable diameter. drill 3 holes: one for the magnet, and two holes with thread, to use for the set screws...

So many ideas and possibilities...

Jesse Open

Is your FA-100 a single or the FA-100T twin?

Sokat

Single.