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Electronic ignition

olyolson

Well Known Member
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Lots of products to choose from- SDS, Electroair, Lightspeed, Lasar, Plasma, Emag and probably lots more I haven't heard of. Been using mags forever and they seem to work just fine. Granted they don't give you the best leaning available but from what I've researched on electronic ignition it only saves you about a gallon an hour fuel burn. Yes it does sound like it makes starting easier and auto plugs are much cheaper.

It does add to the complexity a bit and initial cost is not cheap but overall is it worth the upgrade?
 
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...It does add to the complexity a bit and initial cost is not cheap but overall is it worth the upgrade?

Initial cost actually favors the EI (depending on the system), and long term maintenance costs definitely favors EI (500 hr checks for mags vs ZERO for EI (well, SOME of them anyway))

"Worth it" is mission specific. If looking to go high and long, in my mind its a no brainer. Fuel savings are compelling enough, but the ability to tune the advance to meet all corners of the operating envelope from added detonation margin on takeoff to squeezing out the last knot when high and lean (again, depending on the system) is more than icing on the cake.

Even if you only plan to do 1/2 hour acro missions full rich and WOT, the initial cost of aquisition would favor the EI slightly in my mind, but dumping existing mags for the upgrade would be a tough call. That is, until that 500 hour inspection comes due and you find you need points, a distributor block and a coil.
 
Oly, I think it depends on the mission. I've found it worthwhile, and I am arguably picky about engines. I would not (for example) bother with it for an A-65 on a Baby Ace. If you're flying a simple RV on pleasant little fun flights, I'd again say don't bother.

Easier start and much better hot idle seem to be universal for all the EI's. I would not consider all the choices interchangable beyond that level.
 
I agree with both Dan's and Mike's comments above.

One other advantage is that you can get much lower idle speeds with EI's installed. This is important to seaplane pilots but not critical to most RV pilots.

Reliability is another decision point used to justify installing an EI. Would I pull out two working mags? Probably not but I would replace one and save the mag until the other one failed. At that time I would look at putting in a second EI.

If I had a new engine that didn't have an ignition, I would look at the dual system of your choosing.
 
Wow thanks for the great replies guys. Thinking about putting something on one side of a new Angle valve IO-360. I hesitant to say this but the Emag seems to be the easiest to install but having only used mags I really have no basis, just reading the manuals.

Ok here?s to opening a can of worms- Any opinions on which one is the easiest to install/easiest to use/best performing?
 
Ok here’s to opening a can of worms- Any opinions on which one is the easiest to install/easiest to use/best performing?

Easiest to install and use is probably the new Surefly...a swap-in for a Slick mag: https://www.surefly.net/

Best bang for the buck? A Ford EDIS-based system. You'll need to DIY a toothed trigger wheel of some kind. A pickup for it is less than $50. The Ford EDIS module has been about $100 on Ebay. A coil pack is roughly $50, plus you need plug wires, plugs, and plug adapters. The Megajolt controller is $199. Full access to dual maps via laptop. Swap maps on the fly with a panel toggle. A rev limiter is free, along with a bunch of other features. Should the Megajolt quit stone dead, the EDIS brick simply reverts to 10 BTDC.

http://www.vansairforce.com/community/showthread.php?t=135476
 
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Wow thanks for the great replies guys. Thinking about putting something on one side of a new Angle valve IO-360. I hesitant to say this but the Emag seems to be the easiest to install but having only used mags I really have no basis, just reading the manuals.

Ok here?s to opening a can of worms- Any opinions on which one is the easiest to install/easiest to use/best performing?

pMag. 700 hrs with dual pMags on an IO-360. Performance has been flawless. Bought a IO-360M1B from Van?s for the new project with a pMag on one side and an empty hole on the other - soon to be filled with the second pMag.

Carl
 
Wow thanks for the great replies guys. Thinking about putting something on one side of a new Angle valve IO-360. I hesitant to say this but the Emag seems to be the easiest to install but having only used mags I really have no basis, just reading the manuals.

Ok here?s to opening a can of worms- Any opinions on which one is the easiest to install/easiest to use/best performing?

Hi Oly,
Been running eMags for a couple years on my 0-320 RV6A. The thing I like most about these (besides the aforementioned performance benefits) is the self powering feature after you start your engine. I didn't feel like I needed to upgrade my electrical system to run them safely.

btw, I'm the guy who came up to you at 1H0 last month on a Tuesday evening when you were trying to get out before the storm came through. Again nice to meet you.
 
One more opinion

Pmags:
Easy to install and time,about the size of mags.
Redundacy,both Pmags run off the buss or the internal power supply, so 3 sources of electrons to get on the ground.
A negative is mechanical guts like a magneto and electronics bolted to hot engine.
Timing curves are relatively fixed but I have had excellent behavior on my 7:1 0320.
SDS CPI / CPI2 :
Proven electronics that reside AFT of the firewall, and only the proven coils and flywheel timing sensors are FWF, ie no moving/wearing parts.
Spark timing is easily optimized for YOUR engine and flying style.Ross sends them with safe (as in magneto) setups that you can start with. You can taylor to your fuel preference with plan B option.
The negative is you need a small (2nd) battery to assure electrons to get on the ground.
There is no comparison between mags and EI for all the reasons mention by others.
 
Wow thanks for the great replies guys. Thinking about putting something on one side of a new Angle valve IO-360. I hesitant to say this but the Emag seems to be the easiest to install but having only used mags I really have no basis, just reading the manuals.

Ok here?s to opening a can of worms- Any opinions on which one is the easiest to install/easiest to use/best performing?

Pmag is probably one of the easiest to install, but then you are stuck with a remove and inspect operation every year just to make sure its holding together. CPI is a touch more trouble to install but is a "once and done" scenario. No moving parts, nothing to wear out. And then there is the well known issue with the aggressive timing curve with Pmag on the angle valve. With CPI, a non issue. Since you are retaining one magneto, the self powered function of the pmag is pretty much moot - you can go with CPI with zero changes to your electrical system.

I have many hours flying behind Pmags and CPI. Pmags are slightly easier to install, but CPI is easier to own, and much better performance.
 
CPI is a touch more trouble to install but is a "once and done" scenario. No moving parts, nothing to wear out. And then there is the well known issue with the aggressive timing curve with Pmag on the angle valve. With CPI, a non issue. Since you are retaining one magneto, the self powered function of the pmag is pretty much moot - you can go with CPI with zero changes to your electrical system..

Installed CPI last year and thought very easy to install. Was a little timid drilling on the flywheel but good instructions and provided drill block made it a non-event.

The ease of a hot starts, to me, is well worth the cost of going to EI. Had 2 years of hot start issues, and a few times of stranded with dead battery, until I put in the CPI and now starts right away every time. Setting user define advance curve is just an added bonus to me but provides at least 10% fuel cost savings even with my flying style of mostly local flying. The fuel savings and the lack of a 500 hour inspection on one mag looks like, cost-wise, I will break even after about 4-5 years.

I also was able to reduce idle by 100-150 rpm which creates less float on landing and has reduced brake wear considerably, based on reduction of brake dust in the wheel pants. Will need to see in a few years if this results in longer brake pad life.
 
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And another data point, I fly with two mags. My GAMI spread is good. A friend with the dual SDS ignition system in his RV10, flies the same speed and fuel flow. His GAMI spread is not quite as good, so maybe he gets and advantage there with the sub-optimal set up. Be interesting to see when we get that sorted.

Chev Vs ford......... YMMV too.
 
And another data point, I fly with two mags. My GAMI spread is good. A friend with the dual SDS ignition system in his RV10, flies the same speed and fuel flow. His GAMI spread is not quite as good, so maybe he gets and advantage there with the sub-optimal set up. Be interesting to see when we get that sorted.

Chev Vs ford......... YMMV too.

Do you guys both fly LOP, and if so, does he use the LOP advance function?

I have shown many times (well, pretty much every time I fly) that my Rocket picks up 3-4 KTAS with the advance switch active. Same fuel flow; more or less speed depending upon switch position. So in practice, if you guys were in formation and went LOP at the same time, he should walk right away from you when he flips the switch. This is assuming he has taken the few minutes required to find the optimal timing for his particular airplane.

This is the real value of the SDS system and why it is a step up from the prior EI products- its not enough to have "an advance"; you need the "correct" advance. Any chance you know what his normal cruise timing is? And what does he use for the LOP advance value?
 
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I don't understand this advance switch thing. I can run up to 100° LoP with my P-mags on a carbureted engine with no issues and don't have to remember to flip a switch when powering up, letting down, etc.

I can see a pilot forgetting to take the ignition out our LoP advance mode and damaging their engine.

What am I missing?
 
David - thinking about this a bit more. You guys can very easily do a "nearly" apples to apples test: Simply lock down the timing of the SDS ship to the data plate values (23 degrees?) and go fly together. Since he would be emulating a magneto equipped airplane, you can compare performance. Then in the same flight, flip the LOP switch to the normal LOP advance value (again, assuming that he has tested and found "optimum"). I would be shocked if the speed difference between the 23 degree setting and the LOP advance setting (probably ~ 35) was LESS than 10 KTAS, even for a big boat like the RV-10.

This test would take less than 10 minutes to accomplish on your next cross country.
 
I don't understand this advance switch thing. I can run up to 100° LoP with my P-mags on a carbureted engine with no issues and don't have to remember to flip a switch when powering up, letting down, etc.

I can see a pilot forgetting to take the ignition out our LoP advance mode and damaging their engine.

What am I missing?

What you are missing is the fact that the required advance dramatically increases once you go past LOP. Since the primary control logic for EI advance is MP and RPM, the ignition has no way to "know" that the engine is LOP and needs this additional advance kick. The SDS adds a user programable "extra" advance on top of the MP and RPM derrived ignition curve. Until there is a way to reliably sense LOP, we have to use the pilot as the "control logic" to flip this switch and boost the timing.

Yes, the engine will run "fine" LOP with the advance topped out by the normal RPM and MP schedule, but the ignition timing is falling short of what the engine really needs. Simply speaking, the timing will be sub optimal. The SDS product allows you to achieve optimal timing, and you will fly faster on the same FF.

Also, the SDS product has this funtion locked out with MP. If you forget to deactivate the switch on the descent, it will automatically drop out on a MP rise. No harm possible from forgetting to flip the switch.
 
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Thanks for the education Mike.

I don't follow the SDS, so have limited knowledge of it's operation.

Next time I fly, I'll bump the advance on the P-mags and see how that works. The EICommander has a little used "On-The-Fly" feature that allows the pilot to bump the advance in flight without resetting the configuration or permanently changing anything.

How much advance have you found to be optimal?
 
" I fly with two mags."

Ah David,

Remember, you do not always fly with two mags ,like the time you had to divert to Flinders Island after an in-flight mag failure WHILE crossing BASS STRAIT :eek: :eek:
( a potential bad day handled well, good job !! )

David has turbo normalised injectors on his RV-10 that gives him repeatably the best gami spread I have seen.

I have not been able to get my gami spread repeatably as good and suspect an intake gasket failure on No 1.
(Ross,I'll talk with you soon about your new intake clamps :))

You can see the effect here where I am effectively flying with a five cylinder engine while LOP at 29 degrees advance. ( 37LPH = 9.7GPH )

aGhaZTjl7dWwcYLQvD182eqOlFhihhGswyQKjRGPMaFKcLFhUgfDnkwNYH9xJdIp-aAg06Wtjtm2rI5rZ0rOZQ66oxxspuzbN7EZVHpxS12MvkSNNtyA2w3on2PEvMLRZ16KKb5lPp_3G-gyfYJuitOPoUZavgahn6pap5lMCVwczTEVslJVa7SC_u7X2gw3gZnrXqthOyLvGVAPPs2Ro3DqMOJn4KFkRfAN57aPCrzBCwhheaH1v01CDNUfG-CMNmwIeRNxXKOzPpRpzHQggEtXn6h7fpgRoYDH14yKA4cwduuukGB9epXqd7-FEGgNoT6DuBQacPpMOAZM_CmG7-iMZo-Kl2sHTIHISUqJt1JWgdf_zvQr_XLRLtKQd1M418aOOM5VyCLzSxpz-DhDgi5OZ6Ms_ZruJB1F07pal3iJ-CNWxEebUhJLDEyXe2twW9Mtl4XQyWMbUbyb9wW3nrTxLZ5jMsbetK82TXXVWkuA9aOWIYvNUrg-zPhaxbaChtAwEf2rw-_GaOM207IbDYYMmDBX0mWLyGnfs2WWqU1MojCwRsIadDCnr4UB11ALdY76k-f86wAuvm8KEFUuyfJt4DNc7TH7MfdohXLjLke5aIs3Dn5LBUnRRifF2BdNPtrTtRY39bars69HPUtB6sm-Wh2n9AOf4w=w894-h670-no


Michael, David and I will probably have a head to head comparison after I sort out my gami spread/induction leak issue some time in the future.

It should also be noted that I also have an exposed A/C Condenser pod mounted on the belly of my aircraft and what difference that makes,I am not sure,but the data point should be recognised that there are very few identical RV-10's to compare with.

It should also be noted how many rotating mechanical parts it takes to keep the old mags running. When I removed my last mag,I was surprised to find the bearing spinning on my mag drive unit verse the ZERO moving parts on the Dual SDS CPI system.

CPI Install write up here,
http://www.vansairforce.com/community/showthread.php?t=140051&page=4

I won't be going back to the "good old mags" anytime soon :D
 
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Thanks for the education Mike.

I don't follow the SDS, so have limited knowledge of it's operation.

Next time I fly, I'll bump the advance on the P-mags and see how that works. The EICommander has a little used "On-The-Fly" feature that allows the pilot to bump the advance in flight without resetting the configuration or permanently changing anything.

How much advance have you found to be optimal?

Bill, I have found that an increase of 4 degrees is optimum for me. Understand that this is AFTER I have found the "optimal" timing for my 8500 cruise altitude "best power" mixture, and also understand I only go about 25 LOP. If you have not optimized your best power advance and/or you are going further LOP, my 4 degree figure is almost meaningless. Your best bet IMHO is to establish your LOP cruise configuration and just keep bumping your timing until you see peak speed. Give the ship a few minutes to settle in to any changes and it should be easy to graph your TAS/timing relationship. You should see a TAS rise, peak, and decline. The further LOP you are, the sharper the peak. Once you have established this peak (optimal timing), compare that to the normal Pmag curve and see how close it is.
 
prop considerations

Another consideration is that adding electronic ignition may affect propeller limitations, or not be a tested or approved combination. There are a number of threads discussing this.
 
?..Michael, David and I will probably have a head to head comparison after I sort out my gami spread/induction leak issue some time in the future.

It should also be noted that I also have an exposed A/C Condenser pod mounted on the belly of my aircraft and what difference that makes,I am not sure,but the data point should be recognised that there are very few identical RV-10's to compare with...


OK. The fact that you are dragging around the AC condenser and you still return the same speed and FF as David is a testament to the efficiency of the SDS ignition. In that respect, a single test of your bird with the "magneto timing" of 23 degrees (or whatever your engine was certified with) compared to the "optimum" timing (as described to Bill above) will tell the tale. Like I said, I'm predicting a +10 knot advantage with the SDS timing optimized.

And yes, grab the SDS intake tube kit. That will solve your leaks.
 
And another data point, I fly with two mags. My GAMI spread is good. A friend with the dual SDS ignition system in his RV10, flies the same speed and fuel flow. His GAMI spread is not quite as good, so maybe he gets and advantage there with the sub-optimal set up. Be interesting to see when we get that sorted.

Chev Vs ford......... YMMV too.

Will be interesting to see how things compare once your friend gets his GAMI spread the same as yours.

Pretty well everyone with EI, reports 1+ GPH less than they had with mags running high and LOP.

Same engine, manifold, CR, prop etc? One plane dirtier/ heavier than the other? I don't see how it's possible for fixed timing to make the same power as optimally advanced timing while running LOP. The flame speed is around 30% slower running 16.5-17AFR than 12.5 ish where best power is made and the mag timing is optimized for.
 
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...I don't see how it's possible for fixed timing to make the same power as optimally advanced timing while running LOP. The flame speed is around 30% slower running 16.5-17AFR than 12.5 ish where best power is made and the mag timing is optimized for.

Yep, this threw me for a loop too. NO WAY an ignition timing of 23 degrees (magnetos) will deliver the same speed as an EI with optimized timing LOP. No way. However, the big difference here is the added drag of the AC condenser, I'd think. That's your smoking gun.
 
You don't always need fuel injection to get good spreads.
This picture was taken in my carbureted O-360 running dual P-mags with an unaltered"A curve" AKA "Jumper in".

KLVJ+to+SC86.jpg
 
You don't always need fuel injection to get good spreads.
This picture was taken in my carbureted O-360 running dual P-mags with an unaltered"A curve" AKA "Jumper in"...

Thats an enviously tight EGT spread. Now go out and find the peak ignition timing and report back with your optimized cruise numbers.
 
Good numbers indeed Bill. Me thinks that -9 wing works better than the 6,7,8 wing does up there.
Absolutely! The -9 wing is stunning. What gets me is that even at that altitude, I was still trimmed nose down. Whereas the short wing RV's are trimmed nose up starting at around 8 to 9 K and above. With the O-360 she stalls in the mid 40's and will cruise right at 200 mph, if I want to put the fuel through her.

About my EGT spread, I have done nothing special to this engine, other than assemble it from an ECi kit. Stock crossover exhaust but it does have a unique FAB of my own design that was required due to the Sam James cowl. I might have just gotten lucky.

Thats an enviously tight EGT spread. Now go out and find the peak ignition timing and report back with your optimized cruise numbers.
Give me a call, let's get together at OSH. I am going for a short flight but probably won't fly until after we get back.
 
...Give me a call, let's get together at OSH. I am going for a short flight but probably won't fly until after we get back.

No OSH for me this year again - otherwise I'd certainly give you a shout. We're just scratching the surface on optimum timing for these engines, so we definitely need more people out there doing methodical flight test. Go get some data and we'll put our heads together.
 
Will be interesting to see how things compare once your friend gets his GAMI spread the same as yours.

Pretty well everyone with EI, reports 1+ GPH less than they had with mags running high and LOP.

Same engine, manifold, CR, prop etc? One plane dirtier/ heavier than the other? I don't see how it's possible for fixed timing to make the same power as optimally advanced timing while running LOP. The flame speed is around 30% slower running 16.5-17AFR than 12.5 ish where best power is made and the mag timing is optimized for.

He needs the upper deck pressured due to ram air effect.

He is coming to see you shortly ;) (AM)

Up high with lean mixtures advance will help, you and I know that, just needs the upper deck turbo style system.
 
Yes, looking forward to meeting Ashley here soon and show him the operation and some of the local SDS installs. He's been a super helpful and friendly guy to deal with as have most of our other Aussie customers.

I'm hoping to make a trip down under in 2019 to check out the aviation scene there and in NZ.
 
Bill, I have found that an increase of 4 degrees is optimum for me. Understand that this is AFTER I have found the "optimal" timing for my 8500 cruise altitude "best power" mixture, and also understand I only go about 25 LOP. If you have not optimized your best power advance and/or you are going further LOP, my 4 degree figure is almost meaningless. Your best bet IMHO is to establish your LOP cruise configuration and just keep bumping your timing until you see peak speed. Give the ship a few minutes to settle in to any changes and it should be easy to graph your TAS/timing relationship. You should see a TAS rise, peak, and decline. The further LOP you are, the sharper the peak. Once you have established this peak (optimal timing), compare that to the normal Pmag curve and see how close it is.

How is this different from the E-Mag EICAD ability to control advance? Seems like it would let you accomplish the same thing.
 
How is this different from the E-Mag EICAD ability to control advance? Seems like it would let you accomplish the same thing.

The EICAD program won't let you play with the P-mag configuration when the engine is running, for that you will need our EICommander.

Other than the tool, it is the same.
 
What is the user interface required to access the "on the fly" feature? Is it a diagnostic screen, or is it meant to actually modify the timing while in flight? And how much can you bump timing - can you go beyond the hard limits imposed by the basic Pmag program? Does it add timing to the existing curve, or does it modify the existing curve?
 
What is the user interface required to access the "on the fly" feature? Is it a diagnostic screen, or is it meant to actually modify the timing while in flight? And how much can you bump timing - can you go beyond the hard limits imposed by the basic Pmag program? Does it add timing to the existing curve, or does it modify the existing curve?

This is an EICommander function only and it must work within the limits of the P-mags.
It has been years since I have played with it and I honestly don't recall the upper limit but seem to think it could be as high as 40, but could be wrong.

This feature does not permanently save the timing to the P-mags and once they power down they the go back to their stored configuration.
 
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OK, so for the purposes of a scientific experiment it sounds like the outcome can be the same. CPI allows more than 40 degrees total, but that's kind of a moot point for 99.9% of us. But as far as a "practical" similarity to the CPI function, it's not the same.

To breister's question, the "LOP advance" is loaded into a user window on the CPI box and is then available with the flip of an external switch. It does not change or go away until/unless you decide to modify it.

To expand on the EICAD function, understand that it does not modify the curve - it simply shifts the entire curve up or down. Not an important distinction you say? Well consider that we know that the standard Pmag curve is more advanced than required at higher power settings. This is shown by flight test as well as loads of anecdotal evidence ("...I installed my Pmags and my CHT it too hot..."). So to solve this issue, we can back off the timing and optimize the engine for higher power ops, but because the whole curve has shifted, it's now far short of the optimum for LOP ops. On the flip side, if you want to optimize for LOP, you would remove the jumper (shifting the curve +5 degrees), or shift it further with the EICAD. You might get what you want for LOP, but you are now WAY too advanced for low altitude, high power. EICAD is a useful tool, but the real limiting factor is the basic Pmag curve.

CPI allows you to build a curve that is as wide and dynamic as your engine needs. This is a fundamental difference from the other products out there.
 
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Sure Fly Electronic Ignition

Sure Fly solid state electronic ignition was developed by the same group that were behind SkyTec starter and the Plane Power alternator out of Texas.

They have both a 4 and 6 cylinder unit that costs an average less than a mag without any maintenance requirements through the TBO of the engine. (2400 for Lyc. & 2000 for Continental) They are announcing at Osh this year their certified units and availability is around the corner....for real.

If you go to www.ameritech-aviation.com, under the electronic tab you can down load a pdf. file on the product.
 
Lots of products to choose from- SDS, Electroair, Lightspeed, Lasar, Plasma, Emag and probably lots more I haven't heard of. Been using mags forever and they seem to work just fine. Granted they don't give you the best leaning available but from what I've researched on electronic ignition it only saves you about a gallon an hour fuel burn. Yes it does sound like it makes starting easier and auto plugs are much cheaper.

It does add to the complexity a bit and initial cost is not cheap but overall is it worth the upgrade?

I chose Lightspeed Plasma III?s mainly for three reasons:
1- Over-rev protection(not a issue for fixed pitch). I?m personally aware of three runaway prop events.
2- Software-free. Discreet logic is hardwired in, so no software and no firmware. I love software, but avoid entrusting my life to it.
3- Precision- the flywheel mini-sensor triggering is ultra precise- whereas gear lash can be an issue with any triggering system run from the accressory case.

The downside is the need for a solid redundant battery backup system, but worth it to me.- Otis
 
Sure Fly solid state electronic ignition was developed by the same group that were behind SkyTec starter and the Plane Power alternator out of Texas.

They have both a 4 and 6 cylinder unit that costs an average less than a mag without any maintenance requirements through the TBO of the engine. (2400 for Lyc. & 2000 for Continental) They are announcing at Osh this year their certified units and availability is around the corner....for real.

But it is stuck at standard Mag timing. No advance feature.
 
I chose Lightspeed Plasma III’s mainly for three reasons:
1- Over-rev protection(not a issue for fixed pitch). I’m personally aware of three runaway prop events.
2- Software-free. Discreet logic is hardwired in, so no software and no firmware. I love software, but avoid entrusting my life to it.
3- Precision- the flywheel mini-sensor triggering is ultra precise- whereas gear lash can be an issue with any triggering system run from the accressory case.

The downside is the need for a solid redundant battery backup system, but worth it to me.- Otis

FYI -

1. P-mags also have a rev limiter, which is adjustable.
2. Software is an advantage as it allows the ignition to be tuned for your application.
3. Flywheel triggers can fail as mentioned in the article I have proved the link to below, even though it is not a Lycoming engine, it is worth reading. Also there was a report a few years back of someone who had a dual LS installation. His alternator belt snapped and took out both trigger wires. The P-mag installation is still the simplest of all the EI's I have seen.

Here is the link I referenced above. If you are going to affix a trigger magnet to your flywheel, please take pains to secure it securely and protect you igntion wires from a catastrophic event.
 
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For what it's worth...

Eastbound last month over central Nevada on my way to my annual fishing trip (yep, big fish in Nevada) in my RV-7, vertical draft IO-360 Superior Lyclone, P/A injection, dual LSE Plasma III ignitions, Hartzell B/A prop, leaned to peak at this altitude. I noodle constantly about the control available with the SDS setup, though being intimately familiar with Ford's EDIS that's tempting too. I have a couple of spare Ford V8 EDIS modules, anyone want to experiment?

i-jFSBJnn-XL.jpg


If you happen to be flying near N15 and have the resources to spend the night, I highly recommend this venue for drinks and camaraderie:

i-c66RSBV-XL.jpg
 
What I'm thinking Bill is that you are in for some flight test when you get back from OSH. I'd like to have you do a few edge case scenarios:

First and foremost, the high, LOP advance. If I'm right, your engine is going to need an additional advance kick beyond the standard P-mag curve, and you will pick up a few knots.

Second, I'd like to see a low altitude, full power speed run. If I'm right, your engine is going to take a significant timing retard from the standard P-mag curve. The speed will stay the same, but the CHT will plummet.

If you want, I'll send you my curve as well as a kneeboard data collection sheet to help document this as you fly.
 
What I'm thinking Bill is that you are in for some flight test when you get back from OSH. I'd like to have you do a few edge case scenarios:

First and foremost, the high, LOP advance. If I'm right, your engine is going to need an additional advance kick beyond the standard P-mag curve, and you will pick up a few knots.

Second, I'd like to see a low altitude, full power speed run. If I'm right, your engine is going to take a significant timing retard from the standard P-mag curve. The speed will stay the same, but the CHT will plummet.

If you want, I'll send you my curve as well as a kneeboard data collection sheet to help document this as you fly.

Nigel already flew the best Pmag timing survey you'll ever get, then published it in Kitplanes, March 2017.
 
Nigel already flew the best Pmag timing survey you'll ever get, then published it in Kitplanes, March 2017.

While that was a good article, Nigel did not use the "on the fly" routine in the EIC, so I will be able to play with the timing a bit more, I hope. We will see. Also, Nigel did not have the stock compression, I do. In fact, my engine is 100% out of the box stock.

Mike, I wonder if when doing the test down low if I'll be able to exceed the Vne. I am only 10 mph away from it at 8000' DA, full throttle, and leaned for best power. I did find at that altitude retarding the timing a little gave me both lower CHT's and a few knots more speed.

I'll give you a call when I get back from OSH. My speed numbers will be different than Nigel's but that is to be expected as I'm flying a different plane. The thing we will look for is the delta for this installation.
 
I chose Lightspeed Plasma III?s mainly for three reasons:
1- Over-rev protection(not a issue for fixed pitch). I?m personally aware of three runaway prop events.
2- Software-free. Discreet logic is hardwired in, so no software and no firmware. I love software, but avoid entrusting my life to it.
3- Precision- the flywheel mini-sensor triggering is ultra precise- whereas gear lash can be an issue with any triggering system run from the accressory case.

The downside is the need for a solid redundant battery backup system, but worth it to me.- Otis

Hi Otis. I have some educated opinions on this.

1. Over rev limitation. I agree.
2. Software vs. discrete logic. I agree in general, but at some point software will be embedded in everything. I am working on a new generation trim and flaps controller that works entirely in hardware, but when a CPU is plugged in, additional features are enabled. In this way, the software driven functions work in parallel with the hardware. Sort of like a 'limp home' mode. I think it's reasonable to ask all of the ignition/ecu vendors that use software if they support such a mode.
3. flywheel triggers gives precise, repeatable ignition timing events, whereas accessory case driven timing has gear lash so the ignition timing is 'dithered' around the ideal timing. This may not be a Bad Thing. Just ask the prop vendors about resonances and electronic ignitions. Dithering may reduce these resonances and is a common technique in electronic systems to reduce radiated emissions. Flywheel triggers have their own failure modes that can be nasty. I have had inflight failures with a flywheel system...Yikes!

There is another issue related to electronic ignitions that needs addressing. Many systems allow you to increase the spark gap on your plugs to provide a 'hotter' spark. This means that the spark plug wires operate at higher voltages and are subject to faster degradation and flash-over (misfire). Routing and separation of these wires is more important. I have found that careful gap control is important... make sure all plugs have the same gap and that the gap never exceeds the allowable specs. In fact, bigger is not necessarily better because modern ignitions have long duration lower voltage sparks, rather than short, high voltage sparks.

V
 
While that was a good article, Nigel did not use the "on the fly" routine in the EIC, so I will be able to play with the timing a bit more, I hope. We will see. Also, Nigel did not have the stock compression, I do. In fact, my engine is 100% out of the box stock...

Right. This is a slightly different presentation of (what should be) complementary data. Always good to have another "tester" in the pool too.

Dan, when you get your multiple map capability up and running will you contribute some data as well? Would be nice to see how the hot rod angle valve with its faster burn combustion chamber responds.
 
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