Electronic ignition

The whole point, to me, is to eliminate the relatively short maintenance interval of the mags, as well as eliminating a common failure point for my only engine. Getting spark advance is a nice bonus, but you're leaving performance on the table by only advancing one spark.

I'm never gonna hand prop my engine. It's 280hp, I think it'd be pretty difficult.

Now, it may be prudent to have two different electronic ignition systems to avoid common mode failures, but mags are just ancient technology and we can do better.

Youre just swapping failure modes, but again if youre only going to possibly get stranded somewhere as backwoods as a uncontrolled field, sure, but if youre landing out where there are no people, reception and where youre not likely walking out, ill hand flip my 520 before I flip the switch on my 406, also I trust my bendix mag more than a electronic computer ignition.

If I was doing reno, acro, or staying local to civilization sure, electronic ignition would be fun
 
Youre just swapping failure modes, but again if youre only going to possibly get stranded somewhere as backwoods as a uncontrolled field, sure, but if youre landing out where there are no people, reception and where youre not likely walking out, ill hand flip my 520 before I flip the switch on my 406, also I trust my bendix mag more than a electronic computer ignition.

If I was doing reno, acro, or staying local to civilization sure, electronic ignition would be fun

I wouldn't say I'm "staying local to civilization" but I'm also not landing in the bush in a Mooney. ;)
 
I see the pros and cons of 2 EIs but I prefer the current setup as the simplicity of the mag, with no real ties to the electrical system, serves as an excellent/reliable backup. The EI provides a hotter spark with variable timing to one spark plug similar to more modern ignition systems. Is there really that much more to be gained by a 2nd plug firing at same time? Don't see too many dual ignition systems in automotive (except in top fuel dragsters and they use magnetos). Bottom line is it worth a slightly better ignition vs safety loss of 2 electrically dependent units?
 
Is there really that much more to be gained by a 2nd plug firing at same time? Don't see too many dual ignition systems in automotive (except in top fuel dragsters and they use magnetos).

Yes. Most aircraft engines were designed with dual ignitions in mind. If there was no advantage to the dual ignition setup you would not see the rpm drop/loss of power that we see when doing a magneto check during runup or in flight.

Some engines, such as the Jabiru, really don’t run any different on one ignition or both. In the jabiru’s case, it is because the spark plugs are side by side so the fire only starts in one place anyway.

In the case of the old dual plug hemis, Triumph motorcycles, Harley’s etc. that use dual plugs, the setup is typically used to combat a sub stellar head design.
 
I read on another thread that there was a 20ms lag when cycling mags. I understand that Surefly was able to reduce the lag time to 2 ms. Mostly eliminating the issue.

I corresponded with Surefly tech support on this issue and here's their response:

"The FAA is working on approving this mod. The issue is that when the mag check is performed, there is a momentary removal of power from the SIM. When power is restored, it takes about 100 milliseconds to reboot, during which time it may have missed about 3 ignition cycles. That is what is causing what sounds like a backfire. The mod will cut that time down to something like 2 milliseconds."

So it's not 20 ms but 100 ms. And the backfire like behavior (going out through the exhaust instead up back thru the carb) can happen. Presumably the change to 2 ms will eliminate that behavior, but it is not available in units currently being sold.

The response did not address my question as to retrofitability, so I re-asked and am waiting for a response.

Overall I am impressed with their forthrightness and will probably get one installed if it can be retrofitted with the mod to shorten the lag. If not, then I'm probably waiting for the updated units to become available.
 
I got a response about whether or not the upgrade is retrofittable. It will be a firmware update that can be applied to existing units. Only downside is that they will have to be removed and sent back to Surefly to have the patch applied.

For me this clinches 2 things. First, I will wait for the update to be approved by the FAA before purchasing and installing, but second, the excellent technical support clinched my decision in favor of getting a Surefly.
 
Two airplanes, two Lycomings, and two Electroaires. One on a O-360 and one on a IO-540.

Count on about $7K installed. Is it worth it? I think I saw the most noticeable improvement on smoothness and climb on the O-360, which is not surprising. I think you will see a moderately improved climb and and fuel burn. Worth 7K?....probably could not make that case.

The other part of it is that I just cannot stand the fact that we don't have the ability to adjust firing timing on these archaic engines. That part bothers me. At least we can move from 1910 technology to 1985 technology, which is generally about where these certified EFI units fall.

The ElectroAir salesman told me my engine can last 3000 hours until TBO with this product. So maybe the money savings is in the extended TBO. I asked him which engine and he said it was a small Lycoming. That information is useless to me when I have IO-470’s but he didn’t have Apple to Apple TBO information for my engine.

I was told $12k for both engine with the ElectroAir. Way too much for me to swallow now after an avionics update and upcoming prop replacements.

I doubt I’ll see the $12k savings. I wanted to see the data where I’d be able to make my money back and he didn’t have that data to give me in our conversation. I’ll be sticking with the old mags for now.


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