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Electronic Ignition Comparison Matrix

CATPart

Well Known Member
I propose WE maintain a chart such as this:

412689628.jpg


Revision 4 is current.
Revision 1 was made off the top of my head, some data may be wrong, and I hoping people will submit corrections in short order.

Please propose additional features to compare, as well as ignition systems I forgot. Please help dig up data to fill the chart.

Blank cell means "probably No but confirm for yourself and report back if it should be a Yes"
Y means "Yes"
? means "a strong probably"

Propose corrections using the Column letter and Row number, such as "D18 should be Yes"

I pretty much know which ignition I want, but this chart might help some other folks.
 
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CPI and EM-5 Corrections

Good idea to compare features at a glance

A and B 6 no 28V version

A and B 7 about 1.6 amps at 2700 rpm.

A and B 8 about 2.4 amps at 2700 rpm.

Maybe you could add a pricing line with complete plug wires, plugs, adapters?
 
Maybe add a line showing how many moving parts.
ie : some EI's have zero moving parts and require zero maintenance
some required periodic checking of their mechanical drives
 
Good idea but there seem to be a number of inaccuracies in that list.

Other things I would like to see are: programmable / custom configurations, adjustable base and max timing, adjustable timing map based on RPM & manifold pressure, RPM based ignition cut off, ignition harness (coil pack, plugs, and wire) health, auto or aircraft plugs & harnesses, ease of installation and timing, custom machining required (flywheel or other parts)?

There are a few other thoughts but that is all I can think of right now.
 
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Not sure how to charactarize it across the board, but both SDS products offer the "LOP advance switch" function. I believe the P200 will also have this feature, though I think its a "retard only" for bad/auto gas.

Both SDS products also offer a user defined "start retard" function.

Both SDS products will run up to 8 cylinders

P-mag is also PC "programmed" (though that is a bit of a misnomer, since the curve can only be shifted)
 
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I made some additions per everyone's comments, see first post.

Dustyone
I find the moving parts suggestion to be difficult, they all have at least one moving part, being the trigger (flying magnets included).

N941WR
Please point out inaccuracies, happy to fix, that's the goal. FWIW I did state that was my intent, to build this as a collective. Also, I originally posted in the temp forum, hoping to vet this out a bit, but it got moved. I added many of your suggestions, however I find "ease of installation and timing" to be subjective and not meeting the objective nature of this exercise. Your input is highly appreciated so keep it coming.

Also, I sort of changed my theory on the usage of question marks. I removed most of them. At this point I consider them to mean "a strong probably". A Y still means yes, but I think a blank should mean "probably no but confirm for yourself and report back if it is a Yes". First day growing pains.
 
rv6ejguy
Pricing is one of those things that is too dynamic and too variable depending on setup. I hesitate to add prices, but maybe something like "approximate price for complete replacement of a single magneto/wires/plugs"?
 
rv6ejguy
Pricing is one of those things that is too dynamic and too variable depending on setup. I hesitate to add prices, but maybe something like "approximate price for complete replacement of a single magneto/wires/plugs"?

Sounds good, but break out the plug costs separately, or add lines for Auto vs Aircraft plugs.
 
A minor contribution - Lightspeed does indeed have a 6 cal version and have had for years. It's only avail with the flywheel timing pickup and does respond to MAP changes. Might be other things but these jumped out at me.
 
27 A and B yes.

29 A and B- no. We don't offer or recommend aircraft plugs or wires with products. Our prices include auto plug adapters, best quality, made in USA MSD 8.5mm wires, stainless terminals and silicone boots plus NGK or Denso plugs. You may also delete those items to get your own locally if desired.

My idea on price was to compare apples to apples with regards to accessing and changing timing information in flight. The other systems which have this capability require expensive aftermarket additions.

All EM-5 systems come with the programmer.
 
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Minor correction/clarification. SDS products have a user programable start retard, while the others offerings are locked out. This is a differentiator for SDS as it allows the user to tune to his particular engine needs i.e. Light prop and slow cranking speeds will like it to fire well after TDC, where a heavy prop and fast starter will like something closer to TDC.

Also not sure what is meant by max advance limiting feature on the P-mag (30-E)?
 
updated to revision 3, see first post.

Some renumbering has taken place as I inserted a new line or two.

Pricing has been added and I think I came up with a way to handle some of the variability. I really don't want to get any more specific than this for now. Maybe I can add 6 cyl pricing too. Note, the Electroair pricing came from their website, but is actually lower on spruce.

Toolbuilder
max advance limiting feature is a protection to prevent timing that will damage your engine. I think you can set an upper limit in the software.

rv6ejguy
I was not sure if you have wires etc included in your prices, please respond accordingly.

az_gila
in my chart, use of adapters (a) implies auto plugs and wires.
 
I think ElectroAir is a Y in D-30

They actually prefer the REM37BY plugs, but with a bigger gap.
 
ok gil and mike, will fix, good catch. I just got it backwards, I meant they don't use automotive plugs/wires, at least I can't find where they say they do. will wait for some more suggestions before I make another rev.
 
updated to revision 3, see first post.

Some renumbering has taken place as I inserted a new line or two.

Pricing has been added and I think I came up with a way to handle some of the variability. I really don't want to get any more specific than this for now. Maybe I can add 6 cyl pricing too. Note, the Electroair pricing came from their website, but is actually lower on spruce.

Toolbuilder
max advance limiting feature is a protection to prevent timing that will damage your engine. I think you can set an upper limit in the software.

rv6ejguy
I was not sure if you have wires etc included in your prices, please respond accordingly.

az_gila
in my chart, use of adapters (a) implies auto plugs and wires.

Yes, plugs, wires, boots, terminals and plug adapters are included in our kit prices.

I'd call 200 A around $3000. Your estimate was remarkably close!

The chart is pretty good now, consolidating a lot of useful information. Thanks for devoting your time to this.
 
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34 D&E are optional

Are you sure you mean 34 D & E, meaning "REQUIRES DRILLING FLYWHEEL FOR TIMING SENSOR MAGNETS for Electro-Air and Pmag"?

I see no option on Pmag for a flywheel trigger, nor do I see drilling in the electroair install manual.
 
E20 Is confusing.

Your matrix makes it sound like the Third Party control head is required, when it is optional and not required for safe operation or configuration.
 
rv6ejguy
What about a price for A100?

N941WR
how about "OPTIONAL 3RD PARTY PANEL MOUNTED PROGRAMMER (EI COMMANDER)"? or I could call it a Control Head if you prefer.
 
Shouldn't 100 E be $1750 to meet the description criteria? $1395 + $75 for plug wire set, $85 for plug adapters and $198 for drive gear. (from P-mags website)

I don't find 20 E confusing. If you want to monitor the P-mag or adjust timing in flight, that optional item is $600 more on top of the hardware listed above. ($2350 total)
 
Are you sure you mean 34 D & E, meaning "REQUIRES DRILLING FLYWHEEL FOR TIMING SENSOR MAGNETS for Electro-Air and Pmag"?

I see no option on Pmag for a flywheel trigger, nor do I see drilling in the electroair install manual.

Opps. reading too fast.. Yes D & G. ElectroAir and Lightspeed can go crank timing or mag housing.
 
rv6ejguy
No for E100. The price is as they list for the options included in that price. I am noting the various included options with (w)(p)(a) in the individual cells. I will modify the description to help clear that up. I have +gear because people often reuse the gear from their old mag, so it is not necessarily an up front cost.

FasGlas
Lightspeed has an accessory case trigger, not a mag trigger. I added a row for it. Also, lightspeed's current crank trigger offering dos not require drilling the flywheel.
 
updated to revision 3, see first post.

Some renumbering has taken place as I inserted a new line or two.

Toolbuilder
max advance limiting feature is a protection to prevent timing that will damage your engine. I think you can set an upper limit in the software...

First off: great work on this matrix!

I think we need to explore this a little more (or get me smarter). Any EI with a variable timing feature will allow timing that can damage your engine. After all, by default, advancing the timing beyond the data plate value is what gives these things their punch, and a malfunction which allows full advance at the wrong time (as reported in another thread with the MAP failure of a Litespeed) is a bad thing. By portaying the P-mag as having a advance limiting feature indicates (to me) that the system can keep track any failure, know the engine power output, and ensure the timing does not advance into detonation. I dont think it does this. I think what it DOES do is simply provide a conservative upper limit which cant be overidden by the user. To me this is like making a "stall proof" airplane by limiting the elevator travel. It works, but performance is limited as a result.
So by the same token, the SDS user can program a very conservative limit in the advance curve and claim the same effect. If this is the case, then you should give credit for this feature to the SDS products.

However, we can go one step further than P-mag with SDS and show a practical advance limit even with a MAP malfunction. Since a MAP sensor apparently usually fails high or low, it is very easy to program all MAP points on either side of your operating "window" to provide zero MP advance. So if the MAP sensor fails high on takeoff roll and would drive another ignition to full advance, the SDS unit sees the hard limit and drops the MAP advance to zero, leaving only the RPM setting (which is the same as the data plate on my engine). So where a hard fail of the MAP can be a disaster on other ignitions, on the SDS it is a non-event. That is the power of having the curve at your fingertips instead of locked down.

So, I have no idea how the above should end up on your chart, but thought it worth mentioning.
 
Toolbuilder,
my take on it...pmag has 2 base curves (A and B curves in pmag lingo). The user has the ability to shift the timing of the entire curve. However, the software also has a user set hard limit to max timing advance. This limit would prevent the user from inadvertently shifting the curves by an amount that would exceed this limit. Because the pmags are a more simplistic approach I think this works well to give the user the ability to make changes without fear of screwing up (assuming the limit is appropriately set).

The other systems that are fully programmable will allow the user to put timing into potentially unsafe ranges. The user must be smarter and understand this should they chose to deviate from the manufacturer supplied curves. I am not aware of a similar sds setting that provides the same overlay of protection as that particular pmag setting.

This particular feature should probably be investigated more thoroughly for all of the EI offerings in the matrix.
 
lightspeed has had the hall effect mag hole sensor for years. G-10

bob burns
RV-4 N82RB
 
Toolbuilder,
my take on it...pmag has 2 base curves (A and B curves in pmag lingo). The user has the ability to shift the timing of the entire curve. However, the software also has a user set hard limit to max timing advance. This limit would prevent the user from inadvertently shifting the curves by an amount that would exceed this limit. Because the pmags are a more simplistic approach I think this works well to give the user the ability to make changes without fear of screwing up (assuming the limit is appropriately set)...

Ok, fair enough. This is the "limited elevator" analogy. I'm not sure I would tout this as a protection method, but hey, that's marketing for you. As long as the potential customers know the background.

As an aside we've recently seen a MAP failure of a Litespeed (and as a result I immediately ran out and changed the programming on my CPI to guard against such a failure); does anybody know if the P-mag MAP sensor behaves the same as the rest?

Not being alarmist, just wondering.
 
rv6ejguy
No for E100. The price is as they list for the options included in that price. I am noting the various included options with (w)(p)(a) in the individual cells. I will modify the description to help clear that up. I have +gear because people often reuse the gear from their old mag, so it is not necessarily an up front cost.

Ok, got it now. Thanks for clarifying.
 
The total rpm advance limit won't be too useful if it exceeds say 32+ degrees or so on your average Lycoming, a lot less if you have higher CR than stock or run mogas. Full throttle at SL on a hot day with CHTs over 380 and that much timing will cause lots 'o detonation anyway. Unless a system limits total advance to something like 24 degrees in the event of a MAP sensor failure, there is not much basis in useful fact for the protection claims.

Limiting total advance to data plate or less is the only way to truly protect from detonation (taking into account CR and octane of course) outside of knock sensors or much smarter monitoring of parameters such as CHT and IAT. These are things the EM-5 can do. The CPI also has a knock sensor input but that input is often used for the advance switch.
 
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updated to revision 4, see first post.

Once a bit more stable I may reorder the features a bit. Also need to find a different picture host because mine resizes to max height of 600 pixels, that's why the text is looking so small.

To sum up this effort, my main goals are to help objectively guide the newcomers and the already savvy, promote general knowledge, eliminate common and redundant questions, prompt more pointed questions.

Captain_John
I totally forgot about G3i! I looked it over and it is conceptually very different and maybe not right for this matrix. But if somebody wants to take a stab at it I can add the info, if it makes sense. I will do some more research too.

rv6ejguy and Toolbuilder,
I think the fact that pmag has the dedicated advance limit setting is the main point. Please don't take my statements of the "protection" this feature offers as gospel, for that was my own interpretation, and not their marketing, my bad for misleading.

everybody else,
thanks for your input thus far.
 
...

However, we can go one step further than P-mag with SDS and show a practical advance limit even with a MAP malfunction. Since a MAP sensor apparently usually fails high or low, it is very easy to program all MAP points on either side of your operating "window" to provide zero MP advance. So if the MAP sensor fails high on takeoff roll and would drive another ignition to full advance, the SDS unit sees the hard limit and drops the MAP advance to zero, leaving only the RPM setting (which is the same as the data plate on my engine). So where a hard fail of the MAP can be a disaster on other ignitions, on the SDS it is a non-event. That is the power of having the curve at your fingertips instead of locked down.

So, I have no idea how the above should end up on your chart, but thought it worth mentioning.

FYI - The P-mags revert to the minimum timing when they lose manifold pressure, not the maximum limit.
 
FYI - The P-mags revert to the minimum timing when they lose manifold pressure, not the maximum limit.

Are you suggesting that their software reads an extreme high or low voltage condition in the MAP sensor, recognizes this as some kind of malfunction and then in turn pulls all the MAP advance off the table? If so, then thats one step ahead of Litespeed, it appears.
 
Are you suggesting that their software reads an extreme high or low voltage condition in the MAP sensor, recognizes this as some kind of malfunction and then in turn pulls all the MAP advance off the table? If so, then thats one step ahead of Litespeed, it appears.

I'm not sure how they measure MAP but I do know if you disconnect the line and leave it open to ambient pressure, it will not advance.
 
Scott, I didn't say anything about Lightspeed, just the P-mag.

The point being, the basic concept of advance based on a sensor has failure modes that can be catastrophic (destroy an engine), way more complicated than a tubing connection coming off. Has everyone accounted for these failure modes? I can prove the answer is No.
 
And thanks to you tracking that problem down, Scott, we're all a little smarter and a lot better prepared.
 
I'm not sure how they measure MAP but I do know if you disconnect the line and leave it open to ambient pressure, it will not advance.

You mean on the ground right? Of course it will advance with altitude even if the line is disconnected.
Tim Andres
 
Gee, no mention of an EDIS based system. Ya'll don't like full featured systems for minimal dollars? Too experimental? ;)

http://www.vansairforce.com/community/showpost.php?p=1060584&postcount=4

DanH
Big fan here. That one was on my mind from the getgo. I thought it worthy to add but was not knowledgeable enough to do it just yet. If you want to submit where the Y's go then I'll add em. Otherwise I will try to figure it out in time. would make a fun addition to the chart.
 
Seems like a good time to update this thread with the some new EIs on the market in the last year or so.

Here's a comparison chart from our site as of July 2019.



Let me know if there are any errors here.

To be fair, it should be mentioned that Pmag and Surefly with their integrated designs, take less time to install than the others here if that is a consideration.

If someone wants to compare in more detail as in the original chart, I'd be happy to supply any information to make that happen.
 
Seems like a good time to update this thread with the some new EIs on the market in the last year or so.

Here's a comparison chart from our site as of July 2019.



Let me know if there are any errors here.

To be fair, it should be mentioned that Pmag and Surefly with their integrated designs, take less time to install than the others here if that is a consideration.

If someone wants to compare in more detail as in the original chart, I'd be happy to supply any information to make that happen.

To have made it more accurate and consistent, for the PMAG, I would have probably marked it as "Extra cost" for Std. User programmable & LOP timing shift, considering both functionality is there only need a tool which cost extra to accomplish it.
 
To have made it more accurate and consistent, for the PMAG, I would have probably marked it as "Extra cost" for Std. User programmable & LOP timing shift, considering both functionality is there only need a tool which cost extra to accomplish it.

Lightspeed and Pmag both offer optional and expensive equipment to observe values and modify existing curves but they are not fully user programmable for custom curves. Yes, you can drop $600-$900 more for to get some of this capability with a Pmag.
 
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