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Looking for Options for Electronic Ignition

For my use I haven't recognized a difference. I believe the benefit of the additional advance in the B curve is to optimize LOP ops. I haven't explored LOP at all. My injection is nicely balanced so the potential is there. I have friends who operate LOP to the point of needing to restrict cooling because their CHTs are so low. I'm not there yet.
 
For the replies, it looks like my original plan on using the Pmags is a sound idea. The low RPM is a slight detractor, but only due to the plane may be on floats. It already is set up to idle very slow with the stock magnetos, so may just replace one so I still have another point of redundancy. Thanks all!!

I don't see an issue with dual electronic ignitions, as long as there is some type of backup power source. Having the internal generator in systems like the P-mags is kind of like extra redundancy. It's better than no backup battery.

Redundancy is good; two separate ignitions, two separate power supplies (such as ships and backup battery), and the ability to power left, right, or both ignitions from either ships battery or backup battery. In spite of most electrical failures, these selections should help you keep the engine running

Web
 
We have experimented with many different types of electronic ignitions for a while now and I think it comes down to the mission of the aircraft. I have dual P-mags on my Clipwing Taylorcraft and am a huge fan. I do have redundant battery but it is very small and also powers my G3X in the event of a failure. I test my P-mags every run up via the switch and they run at idle speed on the internal alternator just fine.

I've used Lightspeed, SkyDynamics (was my favorite but discontinued) and also Surefly. We did a lot of testing on various dynos. I too had good luck with the Lightspeed systems as installed on Cubcrafters airplanes. My only complaint with Lightspeed is the customer service. I overheard the way they were talking to one of my guys and we had a quick come to Jesus moment. I understand there are likely many dummies calling with dumb questions but that is the reason I would never consider their systems on my personal airplane. It was that bad.

Of all these systems I plan to use 1 P-Mag and 1 Slick mag on my Javron build. We found that 1 electronic ignition gave about 90% of the efficiency benefit on the dyno. The magneto just makes sense for my Super Cub because I'd be able to hand prop it in the event of an electrical failure while away from civilization. In doing it this way, I would not run back up battery.

The Surefly is extremely sensitive to grounding and has been the source of some head scratching for many. If I were going certified- this would obviously have to be my choice. I think it is good but the P-mag offers more.
 
The Surefly is extremely sensitive to grounding and has been the source of some head scratching for many. If I were going certified- this would obviously have to be my choice. I think it is good but the P-mag offers more.
If you have the time could you point out the issues.
Thanks,
Mark
 
Mark- The grounding issues I mention are discussed in some detail on the Surefly website here under the *Input Voltage note at https://www.surefly.net/copy-of-home

It's also now covered in the latest revision of the installation instructions.

The applications I speak of where grounding/ noise gave a bit of a problem were both 24 volt aircraft (Newer Cessna 206). Existing magneto switches and wires were attempted to be used as they worked fine with the original magneto install and appeared to be in excellent condition. In both cases replacement of the switch wiring with all shielded wire and going to a different ground location helped a great deal. The issue was eventually reconciled and I assume there have been no further difficulty.

I was involved in a Field Approval a few months ago for a Surefly install on a T-34. I stopped in last week to check on how the install went and how it was working. The mechanic said they had issues with existing aircraft wiring and grounding location. This particular T-34 is a recent restoration with all new wiring and a modern glass panel so that could be a good or a bad thing. I did not inspect the electrical system. I understand they got it working well and I did not get specifics on what the exact cause was. I am happy to follow up and get the exact fix if you would like.
 
I am running a surefly on the left mag only. Only been since spring but so far so good. Instant starting and very smooth at idle. (Again a composite prop so not a low low idle.) Probably 6 to 7 hundred most times. I have not used the varying timing feature because my flying is all low altitude and I just wanted the quick start solid state feature that is built into the elec. mags. I do have backup bat available especially for starting in case of a power loss. Will advise if issues arise if others are interested. I have noticed no changes in cyl temps that others have talked about and I run 10- compression. I am interested in anyone elses experiences with this mag good or bad.
 
I've used Lightspeed, SkyDynamics (was my favorite but discontinued) and also Surefly. We did a lot of testing on various dynos. I too had good luck with the Lightspeed systems as installed on Cubcrafters airplanes. My only complaint with Lightspeed is the customer service. I overheard the way they were talking to one of my guys and we had a quick come to Jesus moment. I understand there are likely many dummies calling with dumb questions but that is the reason I would never consider their systems on my personal airplane. It was that bad.
Been down that road. I kinda looked at it as a sport. Had a Lightspeed ignition not firing on one system on a pretty new FX2 Carbon Cub. It was a PITA because the airplane was at an airport 30 miles away and did not have a lot of experience with this system. I downloaded the manual and started troubleshooting. I determined the crank sensor on that side was not working. I called Klaus at Lightspeed and immediately felt like I was talking to Lars at Oratex, must be a German thing. ;) It took a little while but after I told him my troubleshooting procedure and the results he warmed up to my conclusion and wanted the crank sensor back because he had not had a failure of one before. I called him again when 4 of us were doing an engine swap in the middle of nowhere and we had an ignition issue. He mention something as I was standing on a work stand looking down at the crank sensor, I interrupted him and told him "got it" one of us put the crank sensor bracket on the same as the opposite side instead of mirror image. I told him thanks and that was it. As I was talking to Jim Richmond at Oshkosh a couple came up and engaged in the conversation. Jim introduced me to Klaus and his lady friend. I reminded him of the crank sensor and he remembered. We got in a very interesting conversation about ignition systems horsepower etc. I think it is a great system and I now have another resource since I work on a lot of airplanes with this system. It is kinda like I proved I was worthy and was excepted. Over my lifetime I have learned a lot about mechanical things but even more about people. ;)
 
Steve- good to hear of your experience. You were obviously much more patient and mature than I. Could have been my fault being quick to go into full send mode when I heard one of my guys being spoken to like that. It's funny how I would take a lot more of that than I'd allow to go to my guys.
 
Steve- good to hear of your experience. You were obviously much more patient and mature than I. Could have been my fault being quick to go into full send mode when I heard one of my guys being spoken to like that. It's funny how I would take a lot more of that than I'd allow to go to my guys.
I had been fore warned and was prepared, plus I wanted to fix the airplane, it was cold in a guys tee hangar 30 miles from my heated hangar and all my tools. 8)
 
It took a little while but after I told him my troubleshooting procedure and the results he warmed up to my conclusion and wanted the crank sensor back because he had not had a failure of one before.

I had been involved with that failure via the CC forum and, based on the information available, I diagnosed which sensor channel had failed. Did you ever get any feedback on the failure mode or did Klaus hold fast to the strange idea that his stuff can't fail.
 
I had been involved with that failure via the CC forum and, based on the information available, I diagnosed which sensor channel had failed. Did you ever get any feedback on the failure mode or did Klaus hold fast to the strange idea that his stuff can't fail.
He just said he had not had a crank sensor failure before. I trashed the replacement because I didn't think hard enough about how to set the gap. After doing it with a feeler gauge with the flywheel installed and futzing with it forever. I failed when it got into the timing ring. I called Klaus and he told me about using a depth gauge and measuring the flywheel between the surface where the crank flange sits and the timing ring. The light bulb went off and I started using my machinist square and a feeler gauge to measure the flywheel to timing ring and then from the crankshaft to crank sensor. Sometimes I'm not the sharpest pencil in the drawer and it takes someone else explaining it to me. Usually cost me time and in this case a crank sensor as well. It is proudly displayed on the "Wall of Shame" in my hangar.
 
I’ve had experience with both P-mags and EFII System 32. I currently run the EFII System 32 in my RV-8, and I absolutely love it. I’ll be running it in my current RV-14 project and I’m also planning on running it in my future Javron build. I’d personally never go back to standard old technology mags, carburetor, or mechanical fuel injection. However, I guess like everything else in life, they both have their good and bad points.

P-mags:
The good. They’re simple, easy to time, generate their own power above a certain RPM, advance/retard is based on manifold pressure, can easily be managed with an external EI-Commander, and utilize automotive spark plugs. Bottom line, P-mags are WAY better than standard mags.

The bad. Like magnetos, they’re still a mechanical device that requires attention from time to time. Things can still wear out! The factory use to recommend sending them back in for a health checkup every 100 hours, or at annual time. I think that’s changed now, so I’d confirm the maintenance intervals with them.

EFII System 32 or SDS:
The good. It can take the place of either your ignition system, fuel delivery system,….or both! It’ll bring your old technology air cooled engine into modern times if you utilized it to its full potential of both electronic fuel injection and electronic ignition. Everything is solid state, so there’s no moving parts and nothing to wear out. Advance/retard is variable and is based on manifold pressure. As with other electronic ignitions, Inexpensive automotive spark plugs are used. If the fuel injection portion is taken advantage of, the high pressure fuel rail will always deliver cold fresh fuel, so hot-starts will never be an issue again. Each injector is adjustable/programmable, so you can get the perfect Gami CHT’s. The entire fuel delivery system is automotive gas friendly….both with and without ethanol. I run 91 octane ethanol laced fuel in my 180 hp RV-8 all the time and she runs perfectly fine. I typically cruse at around 10k’ altitude at 2200 RPM, 165 kts TAS, burning 7.5 GPH. That’s some pretty cheap flying!

The bad. Not rally so much as “the bad”, but really more “the careful”. Yes, the aircraft is completely electrically dependent, so the electrical system and wiring MUST be rock solid. It would be highly advisable to run either a backup alternator or backup battery….or both. I personally think a back alternator is probably the better choice. If your electrical system is bulletproof and you have the proper backup systems in place, there’s really nothing “bad” about the EFII system. If you take advantage of its full potential and utilize both its electronic ignition and fuel injection, you’ll have to do some fuel system plumbing work, but once you’ve finished with the product it’ll be well worth it and you’ll never look back at the old school technology again.


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I’ve had experience with both P-mags and EFII System 32.
This? https://www.flyefii.com/system-32/

How does the cost compare to a pair of Pmags and a standard fuel injection system?
My dual Pmag Bendix FI IO-360B will do 7.5 gph at sea level.
The instructions mention 12 volts and 5 circuit breakers with a total of 45 amps of protection. It does not mention what the system current draw is expected to be. My entire airplane draws less than 10 amps.
Having a dedicated alternator on the engine seems like a good proposition with the ship's power as the standby.
Something like this on the engine for power would make sense.
54A8367_1920px-300x300.jpg
https://bandc.com/product/alternator-30-amps-homebuilt-less-gear/ Or this: https://bandc.com/product/alternator-for-m14p-35-amps-homebuilt/#regulator-controller

A small brushless dynamo makes sense.
 
My Airflow Performance FI is excellent as are my Pmags but I’m not running LOP and don’t intend to for most of my flying. For the go-fast guys I’d think the EFII and deep into LOP makes good sense. ROP vs LOP should be a consideration for choosing EI and FI.
 
P-mags:
The good. They’re simple, easy to time, generate their own power above a certain RPM, advance/retard is based on manifold pressure, ....

I would expect RPM to be dominant input to spark timing in this, and any other, electronic ignition system. In stone age car distributors spark advance was controlled by a centrifugal governor and manifold vacuum only became dominant at low power settings. Electronic ignition systems can directly sense rpm from the trigger inputs.
 
This? https://www.flyefii.com/system-32/

How does the cost compare to a pair of Pmags and a standard fuel injection system?
My dual Pmag Bendix FI IO-360B will do 7.5 gph at sea level.
The instructions mention 12 volts and 5 circuit breakers with a total of 45 amps of protection. It does not mention what the system current draw is expected to be. My entire airplane draws less than 10 amps.
Having a dedicated alternator on the engine seems like a good proposition with the ship's power as the standby.
Something like this on the engine for power would make sense.
54A8367_1920px-300x300.jpg
https://bandc.com/product/alternator-30-amps-homebuilt-less-gear/ Or this: https://bandc.com/product/alternator-for-m14p-35-amps-homebuilt/#regulator-controller

A small brushless dynamo makes sense.

I think if you compare the the total expense of your fuel delivery system….carburetor or mechanical fuel injection, plus the cost of duel P-mags, to a complete EFII System 32, I think you’ll find that the EFII is less expensive overall. If you’re planning on sticking with a standard mechanical fuel delivery setup, it may be close to a toss up on price. P-mags aren’t cheep and they’re kind of a one trick pony, whereas the EFII can do everything. I think if I were strictly wanting electronic ignition and not planning for electronic fuel injection, I’d probably just go with the P-mags. I think they’d definitely be easier to install when thinking about the wiring and also the self powering benefit they offer. But, if you’re wanting the whole enchilada, EFII is the way to go. The wiring of the EFII can be a little bit intimidating at first glance, but it’s really not all that bad. For the most part, the harnesses make it plug and play. The one thing I don’t like about how the instructions have you wire the fuel pump(s) relay is the fact that you only have one relay that operates both fuel pumps. I modified my setup a little bit and use two separate relays….one for each pump. I also wired my relays so that power is supplied to the pumps when the relay is in the “normally closed” position rather than the energized position. This way, if the relays were to lose power, main power would still flow through them and the pump(s) would still work. So basically, power is supplied to each one of my fuel pumps when power is “removed” from the relays and the fuel pump(s) are turned off when power is supplied to the relay(s). I have one high quality Honeywell TL series three position D.P. toggle switch that controls both of my fuel pumps. I have it wired as (off/pump1/pump2). The toggle switch then operates both of my fuel pump relays. Everything works really well and as mentioned above, the relays default to the normally closed position if power is taken away. By doing it this way, it gives me a better sense of reliability and redundancy.

The dynamo is a nice compact backup unit and is probably all you’d really need to get you out of a pinch. I personally like a more standard backup alternator that’ll put out a full 30-40 amps. Both B&C and PlanePower make really nice units that plugs into the vacuum pump pad mount. The PlanePower is internally regulated whereas the B&C is externally regulated. I like the B&C and think it’s a more robust unit.


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I would expect RPM to be dominant input to spark timing in this, and any other, electronic ignition system. In stone age car distributors spark advance was controlled by a centrifugal governor and manifold vacuum only became dominant at low power settings. Electronic ignition systems can directly sense rpm from the trigger inputs.

Very true, but MP is also a direct result of RPM’s AND altitude. I think of the entire system as hand and glove and working in concert with each other to provide the proper advance/retard at the current altitude. When I’m flying my RV-8, as I gain altitude, the RPM’s remain constant but the MP continues to decrease with altitude. With that decrease in MP, my ignition slowly advances until it reaches 30* BTDC. With the advice/retard being linked to the MP, it helps keeps me out of the detonation zone.


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They still use load (MP) to compute advance.

We're using an engine that spends a large portion of it's run time with the throttle at a set position. The easiest way to sense the load on the engine is to monitor manifold pressure. An easy way of showing this is to place a vacuum gauge on something like a water pump engine. If you leave the throttle at any position but vary the amount of water put through the pump, you'll see the vacuum vary with load. Same thing if you monitor manifold pressure on a gas powered air compressor. As the compressor fills the air tank and the load increases, the manifold pressure will vary accordingly

This is why aircraft with constant speed props always have manifold pressure gauges. They help you obtain power from your engine and not destroy it in the process. EI and EFII systems monitoring manifold pressures are just doing this automatically.

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I need a 20 amp battery to comply with the Surefire STC electronic mag. Does anyone know of one that can replace my current lightweight battery under the front seat (16-18 amp)? Certified Cub.
 
I am running the Hawker J16. I asked Surefly about this and they just put down the smallest battery they knew of. They are suppose to be revising that.
 
The Odyssey PC925 is the best small battery I know over 20aH. It’d require mods to the seat mount but it’s a great battery.
 
I need a 20 amp battery to comply with the Surefire STC electronic mag. Does anyone know of one that can replace my current lightweight battery under the front seat (16-18 amp)? Certified Cub.

Just read through the install instructions for this. Seems the unit is to be connected to UNSWITCHED battery power and it will draw one milliamp continuously when the engine is not running. Makes me suspect that it may have to do with not leaving a half dead battery after non flying times. I know . . . they 'recommend' keeping it on a trickle charger, but we're dealing with humans here. Has anyone tried to hand prop with this setup (needs one Surefly and one mag, for certified)?

Yet another reason to use a secondary battery with electronic ignition. Besides keeping power on the EI, if master is off for electrical emergency, it could also be used to keep power on the EI without depleting ships battery.

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Yet another reason to use a secondary battery with electronic ignition. Besides keeping power on the EI, if master is off for electrical emergency, it could also be used to keep power on the EI without depleting ships battery.

CubCrafters installs the Light Speed Engineering Plasma ignition modules with primary power independent of Master. The left and right ignition breakers are battery direct. Light Speed claims zero current draw when the ignition ("mag") switch is off but I have not verified that.

There is sufficient current draw with engine not running and "mag" switch not Off to drain the battery overnight. No, I haven't done that yet but seen reports from those who have.

Surprised that Surefly has a constant current drain. What happens if power is removed and then restored? Doesn't the ignition system work?
 
Just read through the install instructions for this. Seems the unit is to be connected to UNSWITCHED battery power and it will draw one milliamp continuously when the engine is not running. Makes me suspect that it may have to do with not leaving a half dead battery after non flying times. I know . . . they 'recommend' keeping it on a trickle charger, but we're dealing with humans here. Has anyone tried to hand prop with this setup (needs one Surefly and one mag, for certified)?
Web

I did not know about the continuous current draw and the need for a trickle charger. I'm curious where that is written. I can tell you that because of the excess humidity we are having in Alaska this summer my Maule has had some extended periods of sit time. I just went out yesterday and it fired up instantly. Also just doing the math on 1 mA continuous draw seems like a non issue for most of us.

As I recall the requirement to an unswitched source is just so you can't accidentally turn it off in flight. Once it's timed you can disconnect the battery without loosing the timing. It will just go through a boot sequence on reconnect that last a few seconds.

As for hand prop concerns, I have not tried it for obvious reasons (3 blade on floats) but I can tell you that the difference in starting response going from two Slicks to a Surefly on the right is amazing. I would guess this would help, unless I'm missing something.

Jerry
 
Screenshots from the airframe install manual.

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