IO-540 Electronic Ignition

[edmo]

I am planning to run an IO-540 with airflow performance in my model B and looking for input on electronic ignition options. I am looking specifically for those that will install in the magneto drive holes and avoid systems that involve sensors up on the flywheel. I believe this pretty much narrows it down to Surefly and Pmag. There is a good write-up on Surefly here, https://bearhawkforums.com/forum/bea...ronic-ignition but very little on the six cylinder Pmag. Likely because they are still new and not many of you are flying with them. There is some information on VAF, but it seems many topics over there get off track, or become and argument. I would really like to go with the Pmag as Surefly requires power, and it sounds like they want it to be wired directly to the battery to be powered at all times. I am planning a standby alternator on the vacuum pad, but was hoping to avoid a second battery. The Surefly seems to have a good track record for reliability. They have been out for a while now and are advertised as needing no maintenance until the engine is torn down. They are also a certified single mag replacement and the basis for the Lycoming EIS if either of those mean anything. The Pmag on the other hand needs to be removed every 100 hours or year, whichever comes first, to check for play in the drive shaft. They are much newer, after many lengthy delays, and at least anecdotally seem to have more problems or at least teething issues. Everything's a compromise and it seems my decision has come down to stand alone operation or perceived reliability. What else am I missing?

So, for those you you running either Surefly or Pmag what are your experiences with the companies, install, and operation of each? Or, what made you choose either one, or decide to avoid both?

[TimTall]

I'm not flying yet but I'm installing dual P-mags on an IO-470. I can't speak to the performance on the 6 cylinder but the company has been great to deal with. There was a service bulletin a couple months ago and they dealt with it quickly. I sent both mags back to Texas, they did the work and had them back to me in a week.

I've been flying a dual P-mag o-360 lycoming quite a bit recently and they perform well. There's very little RPM drop running on one mag. We've tested them with ship power off so they are both running on their internal generators and there is no noticeable difference until below about 900 rpm when they cut out.

The annual removal thing is a little annoying but much less so on a Continental. They sit on top where they are super easy to get at. I'm not sure how that would work on a lycoming. It would be super crappy on my o-320. Probably even a deal breaker for that engine.

[zkelley2]

Ya, it's pretty annoying to pull a mag, but not the end of the world.

The only thing I really don't like about the surfly is they use aircraft spark plugs. There's no reason to use $35-100 plugs on an experimental imo.

[AKKen07]

May I ask why you don’t want a flywheel metered type?

[edmo]

Thanks, I've only heard good things about SDS, so maybe I'll have to give them another look. I don't really need the extra customization of those systems. I was just hoping to get the majority of the benefit of electronic ignition while keeping as much of a simple bolt on solution as I can.

[robcaldwell]

edmo That was my thinking as well. Both SDS and Light Speed have many ancillary and satellite components which, quite frankly, turned me off.

[AKKen07]

I don't know if anybody else is considering Lightspeed - but that is what I am currently installing. It seems like a good system to me and I look forward to using it - BUT - I have run into something that I dislike. I have had questions about the system installation on a couple of instances - where the manual seemed unclear to me - and so I called Lightspeed to clear up my confusion. Klaus (owner) has taken the time to answer my questions but he has been consistently condescending and outright insulting in the process. I have NO experience to back up what I'm trying to do, so I understand that my questions might seem simple to him, but he has been impressively rude. Were I to do this again I would choose a company with better support for those who are learning as they build.

[chuckkemp]

edited -ck

Electroair Electronic Ignition Systems http://www.electroair.net/ Another option though same issue as the SureFly but can use automotive style plugs

SureFly makes a nice unit. For certified aircraft only one can be installed as the single unit is wired directly to the battery and controlled by a single power switch. If you want to install two mag's "then as you stated" you'll need either a vacuum pad driven permanent mag generator or backup battery to supply power in case of a complete electrical failure. Same holds true for the Electroair...

I also don't think a "standby alternator" would be sufficient in case of a main bus failure as it too needs battery voltage to supply field voltage to excite the alternator. The only way to add dual redundancy for this application is to add a backup battery too. However if you used a "permanent mag generator" that supplies voltage without external excitation could be easier implement and provide the power redundancy the electronic mag's would need without a backup battery. quickfacts_sd8_2019.pdf (bandc.com) Don't think you'll ever have a complete bus failure check out Elliott Seguin's recent engine out, gear up landing in the T51 where the battery bus breaker tripped due to excessive current drain from the runaway gear pump motor, fuel boost pump and the rest of the avionics resulting in a complete main bus loss and therefore no power to the V8 engine's electronic ignition causing the engine loss. Without a true redundant power source to the electronic mags you'd be in the same boat. Or the other option is to stick with one traditional mag.

[Bcone1381]

The Surefly Mag can mate up with automative spark plugs in EAB aircraft using this Magneto Harness equipment supplier.

http://www.g3ignition.com/magmod.html

[robcaldwell]

edmo My setup is exactly as you describe. AFP fuel injection, standby alternator on vacuum pad, single battery... I did a whole video on the subject and ultimately decided to go with Slick Mags, for now. I was not comfortable with the new version 1.0 six cylinder PMags. Felt like I was test piloting for PMag. I will wait until I hear positive results and more time and any upgrades or alterations on 6 cylinder PMags before making the switch. Plus, starting with plain ole mags give me a base line for improvement after making the change that I would have not otherwise known.

Here's my ramblings on my ignition system decision... https://youtu.be/5EO0A1ebqrk

[edmo]

Thanks Rob. Like everyone else on here I have been watching and enjoying your videos. If I had to make the decision when you did I would have done the same thing, or gone with Surefly. As mentioned it isn't that big of a deal to do the simple check other than space becomes tight at the back of the 540. To me it more speaks to their confidence in the product that it needs to be inspected so often when not even traditional mags require inspection that often, and other products aren't supposed to need anything until TBO. I believe Lycoming has completed their testing of the Pmag and will now sell an experimental, or at least Thunderbolt, with dual Pmags. So that's at least more outside testing and a vote of confidence in the product.

[robcaldwell]

Is Lycoming also testing the PMag? I know they introduced a new EI system at the 2019 AirVenture, which is actually white labeled by SureFly.

https://www.lycoming.com/LycomingEIS

[edmo]

I think they have been selling four cylinder engines with dual Pmag for a while, and doing testing on the six cylinder version. Within just the last few months, I believe that is now complete and they will install dual Pmags on the six cylinder. The Lycoming EIS is indeed a version of Surefly, but not an exact copy. I was told it eliminates the other required hardware for Surefly, which I assume was referencing the tachometer signal generator and the STC requirement for CHT monitoring capability. The EIS is also tailored to each engine, so depending on which engine you have it would be a different EIS part number. The downside is I believe the EIS are fixed timing except for the 390, no doubt due to the partnership with Cub Crafters using the 390 as mentioned in that press release. That should eventually come to the other models, but it won't be a software type upgrade, you will have to buy a new EIS with spark advance. So, from what I can tell other than the 390, the EIS is a dumbed down version of Surefly that is more like a solid state magneto replacement, although dependent on your electrical system. I'm sure going to fixed timing helped in certification and is also why they don't require CHT or the tach signal generator. For the experimental crowd, it doesn't seem like a worthwhile option.

[AKKen07]

When I bought my engine from Titan/Continental I had the choice of dual Pmags or Lightspeed. Or Mags of course. (IO540)

[Battson]

Ya, it's pretty annoying to pull a mag, but not the end of the world.

The only thing I really don't like about the surfly is they use aircraft spark plugs. There's no reason to use $35-100 plugs on an experimental imo.

I understand the aviation grade plugs cost $10x as much, but they last 10x longer. I understand the automotive plugs need to be changed each year?
Consumables mean more waste etc.

I have the SIM system and it's great. No complaints except it likes a fast spinning starter motor.

[zkelley2]

I understand the aviation grade plugs cost $10x as much, but they last 10x longer. I understand the automotive plugs need to be changed each year?
Consumables mean more waste etc.

I have the SIM system and it's great. No complaints except it likes a fast spinning starter motor.

No, the auto plugs probably last 10x the aviation plugs, especially the iridium ones, they should outlast the engine. They're just so cheap people just toss them rather than even look at them... and if you're running the standard copper for $1.95 each, then sure.

[Battson]

No, the auto plugs probably last 10x the aviation plugs, especially the iridium ones, they should outlast the engine. They're just so cheap people just toss them rather than even look at them... and if you're running the standard copper for $1.95 each, then sure.

Well sure, maybe they could technically last longer but... In reality people throw them away, which was my point. But if you want to provide me with a reference to auto plugs lasting longer (in aviation use) than the 600hrs I got from the last aviation set I had, I'd like to have a look.

There is a lot of advice on the internet which says "I replace all my auto plugs, every year". Yes, maybe only because they are harder to clean the lead out of and gap(?), but still the same result - throw them all away each year. Depending on the quality of plug you run (personally I am not interesting in flying behind $24 of lawnmower plugs) the cost would be broadly similar to using aviation plugs - in some cases more expensive/.. Which is my point. Cost savings appear small to me and the waste is very distasteful. Personally I would rather clean the plugs, use them again and again for a decade or so. If the auto plugs can to this, then I would seriously consider making the transition.

Can anyone who's been running auto plugs for a long time comment on their experience? It is easy to clean out and gap the auto plugs once they are aging?

The auto plugs are tempting for other reasons as the availability in emergency situations and the modern harness is appealing, as Brooks posted above. If one could make them last the distance they would certainly have advantages.

[zkelley2]

Well sure, maybe they could technically last longer but... In reality people throw them away, which was my point. But if you want to provide me with a reference to auto plugs lasting longer (in aviation use) than the 600hrs I got from the last aviation set I had, I'd like to have a look.

There is a lot of advice on the internet which says "I replace all my auto plugs, every year". Yes, maybe only because they are harder to clean the lead out of and gap(?), but still the same result - throw them all away each year. Depending on the quality of plug you run (personally I am not interesting in flying behind $24 of lawnmower plugs) the cost would be broadly similar to using aviation plugs - in some cases more expensive/.. Which is my point. Cost savings appear small to me and the waste is very distasteful. Personally I would rather clean the plugs, use them again and again for a decade or so. If the auto plugs can to this, then I would seriously consider making the transition.

Can anyone who's been running auto plugs for a long time comment on their experience? It is easy to clean out and gap the auto plugs once they are aging?

The auto plugs are tempting for other reasons as the availability in emergency situations and the modern harness is appealing, as Brooks posted above. If one could make them last the distance they would certainly have advantages.

600 hours on aviation plugs is really good. Like really really good. Copper auto plugs pretty regularly make 100k miles without looking at them. That's just short of 4000 hours equivalent. Iridium will usually go 200k miles. About 4 overhauls for a lycoming worth. Even with lead, they don't foul, partly because the get such a hot spark from the coils from last century, instead of the late 1800s tech. They also start at any temperature. -40C and you're going to cause significant wear, doesn't matter, it'll start. Just like your car. It'll ignite almost any mixture. Insanely flooded, it's fine. Insane LOP, it's fine.

I've never had to replace an auto plug. You look at them every annual and put them back in looking like you took them out of the box yesterday. No lead build up, gaping is wildly easier, but it'll be in spec and you don't need to do it because the electrode didn't wear in 100 hours. The last set at 500 hours(different airplane) I re-gapped 1 plug after 500 hours of use. It was copper. I've never gaped an iridium plug. I've never had to clean an auto plug. They just don't build lead. I'll try to remember to take pictures at annual for you this winter. The plugs will have something around 250 hours on them. I'd bet $100 I put them back in after checking gap and nothing else. They'll be untouched since install.

IMO, the $1.95 NGK's are worth $500 a piece in comparison to an aviation champion, if that's what they cost for their reliability. I'm wildly more comfortable behind an NGK than a champion.
I'm all iridium now just because the cost is so minimal, and I wouldn't be surprised if the plugs outlast the airframe.

The other advantage is I can get a coil pack at almost any remote village. It's weeks to get magneto parts or months for an overhaul. But that's mostly moot, since the MTBF on a coil pack is in the millions of hours compared to a magneto that is lucky to make 500. You won't have a coil strand you anywhere. A magneto has and will. When I ran mags, I carried a spare mag, they fail so often. And what are you going to do? Never go home?
Magnetos are the only thing I've ever in about 10,000 hours now had fail in flight and cause the flight to not finish.(the turbo'd airplanes do really bad on one mag and even worse the mag doesn't have to fail traditionally on high altitude pistons, the dumb things need to be pressurized, get a leak and the thing fails. And everything pressurized leaks.) To say I don't trust them is a wild understatement. Trash is the only place for them.

[Hewko]

I'm running irridium plugs in a 0320 with a Pmag. I had changed them once after a few years, there was nothing wrong with them so I probably won't change them again, until they show an issue.

[whee]

Gear lash is the hitch that gets me when looking at EI systems that fit the magneto mount and run off the magneto drive. You can’t really tune the timing curve when gear lash changes the timing by several degrees. But most people don’t or can’t adjust the timing curve so it probably isn’t a concern for the majority of people.

Most guys that stopped by my hangar raised their eyebrows at my electric ignition and auto plugs. They’ve been fine for me. I’m running the cheap NGK copper plugs because that’s when the manufacture recommended. After a 100hrs they looked totally fine; no gapping or cleaning required.

On the flip side; the Slick mags and Champion plugs I had on my Luscombe were trouble free for over 500hrs.

[Battson]

That's all very interesting feedback. I am certainly tempted to make the change.

The oldest reference to auto plugs in aviation use was 600hrs, after I did a web-search, from an article by an AOPA writer. Which puts them on par with the Champ plugs.

My 'new' ignition harness is very old and my plugs are lasting very well (Champion) with dual Surefly SIM mags. I have a near new Bendix-compatible ignition harness if anyone needs one...

I think I will upgrade to the harness mentioned here and auto plugs when the harness or plug set reaches end of life.

The engine is starting to after-fire now and then, especially when running below 1,000 RPM idle when hot and not leaned correctly. I wonder what is causing that, I suspect the ignition system but I don't have enough knowledge to be sure.

[Battson]

Maybe time to clean the injectors again..? Thoughts?

[zkelley2]

It's backfiring while running(like other than just at start) below 1000rpm but only when hot and very rich?

[Battson]

Affirm, sounds like missing / afterfire occasionally (maybe 1 in 30 to 1 in 50 strokes) below 1000 RPM and when hot, never when cold, and worse if rich or lean of peak. I normally keep it as close to the peak stoichiometric ratio as possible for ground ops, but still get an occasional miss below 1000 RPM.