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E-Mag Pirep

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Tankerpilot75

Well Known Member
Having my engine torn down because of a prop strike at AirVenture and part of the inspection is the replacement of the slick magnetos. I’m seriously considering having Popular Grove install dual E-Mag electronic ignition instead of Slick Mags during the rebuild. The cost difference isn’t great at this time.

I like the idea that E-Mag has of having an internal alternator to power the ignition system in case of electrical failure. I’ve also heard that Superior and Lycoming puts E-Mags on their new experimental engines.

My question: iWhat is the VAF consensus on having dual E-Mags and what experience has the community had with the E-Mag product?
 
There are so many threads about this ... but the consensus is:

For ease of use/installation, they are great and get the job done, way better than traditional mags, typically cranks on half prop, no more hot start issues, smooth idle, a bit better efficiency at altitude.

However, there are more tunable systems available. Slightly more complex to install, but if you're an engine geek there are some great options.
 
I really like my Pmag and will seriously consider replacing my right side slick with a second Pmag in a couple hundred hours when the 500 hour is due.

Pros
-starts easy
-efficiency gain
-self powering
-Using auto-plugs, awesome! Cheap to replace about every 100 hours, never foul up.
-very easy to time

Cons
-your CHTs will go up a very noticeable amount so if you are borderline now, well... You can retard them a few degrees and it will make a very noticeable reduction in CHTs
-100 hour inspection. Every 100 hours you have to take them off the engine and check the shaft for any play, ripple feel, re-time, etc. etc. It's not that big of a deal but it is annoying for sure.
-many people agree that the timing curve is a bit aggressive (also why many people retard a few degrees)

Like Bill said, there are a ton of threads you could read for hours if you wanted to. Great for the set and forget minded person, not the person that wants to tune and tune and tune.
 
I have dual pMags running for close to 20 years on my first RV (8A) and now have 300+ hours on a dual pMag install on my RV-8. There is also a six cylinder pMag running on my old RV-10 and I ordered my new RV-10 engine with dual pMags.

I offer my strongest recommendation for dual pMag install. The engine starts on a blade and it will run smooth deep into LOP - all the way to the point the fan stops. Like some other electronic ignition options the timing advance for typical cross country settings yields a reduction in fuel burn compared to a mag. Full power for takeoff remains at about what you get with a mag. The joy of never needing to clean aviation plugs is a big bonus.

The other big advantage of pMag over the other electronic ignition options is the pMag eliminates the required ship power back up as pMag generates its own power.

There is a lot of talk about needing an EI Commander. For the vast majority of RV installs I consider this unnecessary.

I recommend following the install instructions to set the timing, and run with the jumper in (limits advance to a maximum of 9 degrees from whatever you set as the base timing).

Carl
 
I have dual p-mags, easy start, cheap plugs, super easy starts but the CHT runs hotter even timed a couple degrees retarded.
I would recommend dual.
 
Are you building your airplane on consensus? Seriously, there is so much information out there and so much competition in the decades since the Emag product hit the scene that this is not the forum to make a decision.

What is the mission statement for your ignition? Figure that out and then you can see if the emag aligns. If not, find another product.

You want a quick and dirty? Pmags will often give better performance than magnetos, but have similar (or increased) maintenance requirements. But they have a fixed ignition curve which may or may not suit your engine or how you operate your engine. More modern ignitions offer far more flexibility and versatility which will almost certainly fit your mission.

But Homework is required.
 
Love them

I've had two P MAgs on my RV-4 since it first flew in 2009. Easy to install, simple to wire, easy to run, and no extra power required for backup. For MY mission this is perfect. Like others have said, look at what you are hoping to do, and determine if this is the best solution.

I wanted something that would do the following, or be:

- Easy to install
- Save some fuel
- Not require backup power
- Make starts easy
- Easy to maintain

I wasn't too interested in getting into the weeds on really tweaking my ignition system for absolute optimum performance. I think other systems can give you more performance or flexibility, but I'm no expert.
 
My RV-6 has had dual P-Mags for about 7 years. They have performed flawlessly. Prior I had a Lightspeed for my right mag for 15 years and it performed flawlessly.

I am planning to use dual Lightspeed on my RV-9. I've decided the complexity of a dual electrical system is less than the P-Mag mechanical complexity. I'll also gain extra space between the engine and firewall.

My experience is either Lightspeed or P-Mag will do the job very well.
 
I installed dual P-Mags a year ago at a cost of about 4,000 dollars. My Bendix mags was working flawlessly but had over 500 hrs since rebuild. My engine always started and hot started good with the Bendix mags and do well with the P-Mags also. I have the jumpers in and timed at 0 degrees. I do have to pay more attention to my CHTs taking off with a hot engine. I am cruising 160 kts on 7.1 gph as opposed to 8.0 with the Bendix Mags so I am recouping some of my investment!
 
I have dual p-mags, easy start, cheap plugs, super easy starts but the CHT runs hotter even timed a couple degrees retarded.
I would recommend dual.

How much of a CHT increase should I expect?

As for Toolbuilder’s comment, no I’m not making my decision by consensus but I am seeking information since I have an opportunity to make an ignition system change at an economical price due to engine tear down protocols.

Surefly (and I guess LightSpeed) have electronic ignition systems that also look attractive but require battery backup systems. Space for that is limited on my firewall and does add additional complexity which increases the cost of changing. Magnetos are reliable but I’ve even heard Mike Bush suggest electronic ignition for aircraft engines is both modern and better.

I’m seeking VAF community insights to help me weight the pros and cons of this decision. Thanks!
 
Are you building your airplane on consensus? Seriously, there is so much information out there and so much competition in the decades since the Emag product hit the scene that this is not the forum to make a decision.

What is the mission statement for your ignition? Figure that out and then you can see if the emag aligns. If not, find another product.

You want a quick and dirty? Pmags will often give better performance than magnetos, but have similar (or increased) maintenance requirements. But they have a fixed ignition curve which may or may not suit your engine or how you operate your engine. More modern ignitions offer far more flexibility and versatility which will almost certainly fit your mission.

But Homework is required.

+1

I did not choose Pmags based upon all of the information posted here. I chose a more reliable and more tunable solution similar to the SDS system. Another vote to do your homework first.

Larry
 
How much of a CHT increase should I expect?

...

I’m seeking VAF community insights to help me weight the pros and cons of this decision. Thanks!

If you time the pmag ignitions differently, the CHTs can be lower. It's up to you. Contrary to others, I strongly recommend having a way to see what's going on in the pmag ignitions - there are two products that do this, the enginebridge and the eicommander. I have the eicommander and it gives me real-time info about the timing, and how happy the pmag ignitions are. Not to mention the guy that created it, Bill, is very helpful with any questions about the pmag ignitions.

Timing the pmag ignitions is very easy, once you have read the book and understand what you are doing. Adjusting the timing is a bit more complex, but the documentation is there.

If you are looking for set and forget and never think about it, I recommend getting a regular mag. If you want to understand a bit more, then the pmag is great. If you want to dive in and really tune everything, and are comfortable with electrons, I'd talk to Ross or Robert.
 
Magnetos are reliable but I’ve even heard Mike Bush suggest electronic ignition for aircraft engines is both modern and better.

I’m seeking VAF community insights to help me weight the pros and cons of this decision. Thanks!

I am not sure that Pmags are anymore reliable than mags. My hanger neighbor just had his Pmag die and had to send it in for repair at well less than 500 hours. Similar stories out there - search for bearing failures. Asking for opinions is not the same as searching for the stories that will paint a picture of reliability and other issues, such as the high CHTs caused by overly agressive timing maps that cannot be adjusted for the operating conditions.

If you are hooked on built in elec b/u then P mag is the only option. However, it has drawbacks too, such as losing that b/u if the RPMs fall below around 800 and won't re energize. Thank about pulling the throttle back on final and then needing to go around. Small SLA batteries cost $25 and are very easy to install. The SDS system even has built in circuitry for charging and using it; Just wire the small battery to their box. Couldn't be easier. You can also do one mag and one EI, then no worries about power source.

Not trying to push my bias here, just trying to drive you to do the research. You have many choices today, however, Caveat Emptor still applies.

Larry
 
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I am not sure that Pmags are anymore reliable than mags.

Asking for opinions is not the same as searching for the stories that will paint a picture of reliability and other issues, such as the high CHTs caused by overly agressive timing maps that cannot be adjusted for the operating conditions.

Think about pulling the throttle back on final and then needing to go around.

A couple notes:

Regarding reliability; agree that PMags seem to be as reliable as dinosaur mags, with the added benefits mentioned

Haven't heard of any high CHT issues, sounds more like a cooling problem. I can climb at full power to 10,000 on a 105 degree F humid day here in Alabama and never hit 385. About the only time I can exceed 385 is if I'm dragging it around at 75kts trying to "keep up" with my buddies in cubs, etc. Will definitely heat up then due to the lack of airflow over the cylinders, I usually have to break off to get it cooled down. Not really a PMag specific thing.

Talking about the PMag generators only working above 800rpm, true, but your ship power happily picks up the slack. However, try getting your prop below 1000 rpm on final, not sure it's possible.
 
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A couple notes:

Regarding reliability; agree that PMags seem to be as reliable as dinosaur mags, with the added benefits mentioned

Haven't heard of any high CHT issues, sounds more like a cooling problem. I can climb at full power to 10,000 on a 105 degree F humid day here in Alabama and never hit 385. About the only time I can exceed 385 is if I'm dragging it around at 75kts trying to "keep up" with my buddies in cubs, etc. Will definitely heat up then due to the lack of airflow over the cylinders, I usually have to break off to get it cooled down. Not really a PMag specific thing.

Talking about the PMag generators only working above 800rpm, true, but your ship power happily picks up the slack. However, try getting your prop below 1000 rpm on final, not sure it's possible.

Bill aren't you also running an IO-390 timed to 20 degrees? I thought those engines naturally run a little cooler

I have a well done baffle system on my engine and if my Pmag is timed at TDC on my IO-360 in those conditions I will approach 400 easily in climb. I took out about 4 degrees of timing recently and my CHTs now top out around 385 in hot conditions on climb. I have even started climbing at a slightly slower speed too so the heat reduction was very noticeable indeed.
 
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Bill aren't you also running an IO-390 timed to 20 degrees? I thought those engines naturally run a little cooler

I have a well done baffle system on my engine and if my Pmag is timed at 25 degrees on my IO-360 in those conditions I will approach 400 easily. I took out about 4 degrees of timing recently and my CHTs now top out around 385 in hot conditions. I have even started climbing at a slightly slower speed too so the heat reduction was very noticeable indeed.

I am, and in fairness to the topic, most of the RV folks I talk on a regular basis to are 14 builders or flyers.
 
As I said before, there are hundreds of threads on this site debating this exact question. One even has a "comparison matrix" built in which lists features and price and other pertinent data.

Lets throw out some facts, most of which are gleaned from those threads:

The Pmag initial curve is more aggressive than required for most engines, especially the AV. It is that "over" advance that drives much of the newly dscovered CHT issues.

The Pmag is maintenance intensive. It has many moving parts which need to be inspected every annual. Per the user manual, that inspection requires removal from the airplane.

"Back up power" for any dedicated EI that I know of is very modest indeed. As an example, The SDS CPI pulls slightly over 1.5 amps for a 540 at max RPM. I have measured this in flight. It does not take much of a battery to provide that low current draw for many many hours. The existing ships battery would fly that for days. Your "back up power" plan could be as simple as wiring the ignition directly to the existing battery.

PMags work "fine" for most people (just like magnetos) but they are pretty old school and have been eclipsed in the decades since they came out. If you really, really HAVE to stick with the "self powered" feature, then my advice is to stick with a mag in one hole to satisfy the security blanket issue, and go with SDS CPI on the other side, wired direct to the battery. It's flexibility will overcome the limited curve offered by the Pmag or other ignitions, and allow pretty much the full benefit of the most capable ignition system out there. Just make sure to order the dual hall sensor pickup so you dont have to change it out when you decide to dump the mag for good.
 
Some thoughts:
- CHTs. Yep - get more power out of a cylinder and CHTs go up. Take the timing too far advanced and the CHTs goes up. PMags are close to base timing (whatever you set them at) on take off and full power - so results will be very close to a mag set at that same timing. My many years of flying behind pMags demonstrate no issue with CHTs compared with a mag. I run the pMags (parallel valve 180hp IO-360) at base timing of 25 degrees with the pMag jumper in.
- CHTs. In LOP cruise I routinely get CHTs below 350 degrees in summer. Following Mike Busch’s Lycoming stuck valve guidance, I tend to add fuel to get to closer to peak EGT to keep CHTs around 350 (this also provides an excuse to burn a little more fuel and go faster). Here is his article on the subject:
https://resources.savvyaviation.com...ticles_aopa/AOPA_2020-07_why-valves-stick.pdf
- There is intrinsic value in having engines that run without excessive pilot interaction. While I’m sure there is a covey of pilots that want to tweak engine parameters on a real time basis, I suggest for most there is little practical benefits on engine power or efficiency compared to dual pMags and a balanced traditional fuel injection system. But shoot fire - build what you want, just take with a grain of salt the “this is required” opinions.
- I’ve read most of the ship power dependent electronic ignition install manuals. I have no doubt these systems work as advertised. Considering my experience “fixing” electrical stuff in other experimental builds I fear only a minority of builders using ship power dependent installs produce a redundant power distribution design to keep the fan running for at least a couple of hours (bare minimum for my mission needs) after any single component, wire, breaker, solenoid, switch, junction, etc. failure. I’ve found ship power dependent dual EI installs with the back up battery (installed per the EI manufacture’s guidance) below 2vdc terminal voltage. The list goes on.

So my strong recommendation is to view your ship as a system with components that interact. Adding something without careful study of the impact on the rest of the system is how bad things happen. This is especially true for our modern IFR avionics and ship power dependent engines.

Side note. My first build had dual ship dependent EIs. I found the backup power recommendations in the install manual not adequate, and designed my own system and then tested it for the most practical electrical system failures. It worked as designed. But, that system was removed and replaced with dual pMags after 300 hours. I experienced multiple problems with them - driving the move to pMags

Carl
 
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Are you building your airplane on consensus?……But Homework is required.

Of course, one key component in doing one’s homework on a Van’s RV maintenance topic is a post on VAF asking for opinions from the many knowledgeable folks here. I wouldn’t view that as building my airplane on consensus, but rather using that consensus as a starting point in doing my homework.
 
Of course, one key component in doing one’s homework on a Van’s RV maintenance topic is a post on VAF asking for opinions from the many knowledgeable folks here. I wouldn’t view that as building my airplane on consensus, but rather using that consensus as a starting point in doing my homework.

That's kinda what I was thinking when someone objected to the initial question.

I've got a single pMag and a Bendix mag on my RV-3. Works just fine as far as I'm concerned. I did experience hot CHTs on my new somewhat enhanced engine rebuild until I de-tuned the timing curve by about 3-4 degrees.

My theory is that the lower compression B-flat engines with zero mods that spend most of their time at sea level can probably get away with the stock pMag timing installation at 0 degrees. The higher your field elevation and the more modified your engine, the more you'll want to de-tune the timing curve by timing the mag at something after 0 degrees. My engine has slightly higher compression and a Stage III cam. My home airport is 5,000'MSL. When I researched this several years ago, I was told that the timing advance starts at 25" of manifold pressure. For most folks, this is well into the climb or maybe even a cruise altitude. For me, it's usually a couple hundred feet subterranean!

Yesterday, I climbed from 5,000 field elevation to 14,500'MSL and just barely hit 400 degrees CHT. This morning I climbed from 6,800 field elevation to 13,500'MSL and made it to 395 before leveling off.

At 14,500'MSL (about 15,750 density altitude) I was burning about 5.7gph truing out at 165 knots. Not too shabby for a little RV-3 with an IO-320!
 
Some thoughts:
- CHTs. Yep - get more power out of a cylinder and CHTs go up. Take the timing too far advanced and the CHTs goes up. PMags are close to base timing (whatever you set them at) on take off and full power - so results will be very close to a mag set at that same timing.

Carl

That is not really correct. As the plane climbs, the MAP naturally decreases as the altitude grows, even when WOT. By about 7K, you are below 25" and the advance starts increasing. HOWEVER, most pilots are still ROP at this point and 25* or a bit less is a much better setting when ROP at 25". The higher the climb the greater the advance (the table gives greater and greater advance as the MAP drops), even though it is not helping performance. It is just raising temps. Level off in cruise and go LOP, THEN the advance provides benefits. If you climb LOP, this does not apply.

When I used an advance map similar to what Pmag uses (didn't fully understand the issue at the time), I would start to see CHTs rise to undesirable levels once I got to 7 or 8K and would get worse and worse the higher I climbed until I leveled off and went LOP. I now use 21-25* (same as a mag) when ROP and all CHT issues went away (reductions of 40 degrees) with no performance drop. Simply put, advance levels beyond 25* are only beneficial when Peak or leaner and detrimental when at best power or richer.

If you reduce the base timing then the CHT problems when ROP go away, but you are also now less advanced in cruise and have given up part of the benefit of increased timing advance in the dominant flight configuration.

This is one of the key flaws with preset advance maps. They have no method of determining how rich or lean the mixture is and mixture has the greatest impact on optimal advance, as mixture predominately dictates the flame front travel speed. The best way to overcome this is wtth an EI product that lets you tell the system whether you are LOP or ROP and alter the tables accordingly. This is how auto systems work. They control both fuel and ignition, so can tailor the advance to the current mixture level.

Larry
 
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Of course, one key component in doing one’s homework on a Van’s RV maintenance topic is a post on VAF asking for opinions from the many knowledgeable folks here. I wouldn’t view that as building my airplane on consensus, but rather using that consensus as a starting point in doing my homework.

Many of the posters on this forum are very, very forthcoming with data and educated advice. Those posts exist today, and are available for the reading for anyone to take the few moments to do a simple search. The OP asked, by name, for a "consensus".

I can tell you for a fact that the opinions I have posted in this thread are a result of a lot of avgas burned a lot of discrete data collected, and have been posted many times before. A search will uncover my and other posts directly related to this subject. To start yet another thread as the begining of "homework" is a bit "disrespectful" to those of us who have taken the time to collect, reduce and present flight test data countless times over the years.
 
I break down EI systems into two camps.

1. Direct Mag replacement. The unit goes into the mag hole and uses the gears for timing.

2. Replace mag system. The unit goes in the cockpit with coils mounted on the engine or firewall with a crank position trigger.

System 1 has electronics bolted to a hot vibrating thing and depends on bearings/gears/etc. The best one is probably a pmag because it has a generator to eliminate the need for backup power and it's very popular.

System 2 has electronics insulated from the hot vibrating thing and only mechanically depend on a crank position trigger which is a magnet passing a sensor. The best one is probably the SDS CDI 2 because it has the ability to hookup a small backup battery that is completely separate from the rest of your electrical system and the unit maintains it.

So, what makes you feel more comfortable? A backup generator bolted to a hot engine or a backup battery in the cockpit? Making the argument that one doesn't depend on electrons is not true, they both do.

Also, Would you rather not know what your timing is or purchase an external box, or would you like the programming and timing right on the panel? Would you rather inspect the unit on the back of the engine and periodically pull it to look at bearings/etc or would you rather inspect the crank sensor and wires at the prop?

Once I considered these things I knew which system I wanted.

schu
 
Of course, one key component in doing one’s homework on a Van’s RV maintenance topic is a post on VAF asking for opinions from the many knowledgeable folks here. I wouldn’t view that as building my airplane on consensus, but rather using that consensus as a starting point in doing my homework.

What he said.

For those of you who say “do your homework”, that is what this site is for me. A jumping off point. Personally I’m not a mechanic and have no experience with engines at all. And everything I know is all jets (don’t even know what LoP means yet!) In fact, though I’m far from making this decision, it has mulled over me. So I come here and usually use the search function. When I don’t find what I’m looking for I ask the question. A simple response like “look at power plants and there was a good discussion on this about 8 months ago” would suffice.

If you don’t want to answer than just don’t. Nobody is making you reply to any post. The reason this place works is that usually someone will and it will either be with an answer based on their experience or some advice on where to look. Also, realize that most post are hidden after six months and if you use the pull down you can see older ones (something I just learned).

This site doesn’t work when the reply is “do your research”.

JMHO.
 
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... Also, realize that most post are hidden after six months and if you use the pull down you can see older ones (something I just learned)...

FYI, if you click "User CP" you'll see "Edit Options" listed on the left under "Settings and Options."

You can change the "Default Threads Age Cut Off" to "Show all threads."

Also, you can choose to receive email notification of new Private Messages (and thread subscriptions). I mention this because I think many users are unaware. They post things like "I don't check the forum often" or they simply never open a message that's sitting in their Inbox.


Options.jpg
 
I’ve appreciated the responses received to my initial request for PMag PIREP information. However I have been somewhat offended by the responder who claimed the post was “disrespectful” of their previous posting efforts. Frankly, if everyone who had a question searched every previous posting on this forum there would be fewer and fewer postings and information exchanged.

I’m not an engineer, nor a serious wrench jockey. I am someone who wants his RV to perform the best it can within my realm of affordability and capabilities to maintain and operate. I’ve gleamed a lot of information from this thread - as is the purpose of the forum and made a decision to go with dual PMags on the rebuild. If CHTs become a problem then at least I have a better idea of the probable cause and possible solution.

My request is simple. Be respectful of an OP’s question. Maybe they’re not the expert you are but being willing to politely share your knowledge and possibly educate them is what’s important. Moderator, please close this thread!
 
I’ve appreciated the responses received to my initial request for PMag PIREP information. However I have been somewhat offended by the responder who claimed the post was “disrespectful” of their previous posting efforts. Frankly, if everyone who had a question searched every previous posting on this forum there would be fewer and fewer postings and information exchanged.

I’m not an engineer, nor a serious wrench jockey. I am someone who wants his RV to perform the best it can within my realm of affordability and capabilities to maintain and operate. I’ve gleamed a lot of information from this thread - as is the purpose of the forum and made a decision to go with dual PMags on the rebuild. If CHTs become a problem then at least I have a better idea of the probable cause and possible solution.

My request is simple. Be respectful of an OP’s question. Maybe they’re not the expert you are but being willing to politely share your knowledge and possibly educate them is what’s important. Moderator, please close this thread!
Before it gets close, I just want to say well said here, I completely concur.
 
Many of the posters on this forum are very, very forthcoming with data and educated advice. Those posts exist today, and are available for the reading for anyone to take the few moments to do a simple search. The OP asked, by name, for a "consensus".

Many of the posters on this forum are very, very new at airplane building/maintenance and new to this forum. The search that some think is so “simple” for them is impaired for the newbie by the “you don’t know what you don’t know” concept, not to mention cumbersome limitations imposed by vBulletin’s arcane search engine. It would seem reasonable to hope that if an “expert” would take the time to read the post and type the response “do a search”, maybe he could help out a less knowledgeable poster and take a little extra time and provide a link. Otherwise…maybe just skip over the post altogether….always an option.
 
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.......on my engine and if my Pmag is timed at 25 degrees on my IO-360 in those conditions I will approach 400 easily in climb. I took out about 4 degrees of timing recently and my CHTs now top out around 385 in hot conditions on climb.

Pretty sure eMag timing is at TDC or 1-6 degrees after TC.

Straight from page 14 of their manual:

"Note 1: Be wary of old magneto timing habits. Magnetos are timed using the 25 degree (or other) BTDC marks. Here, you will time at TDC or slightly after (never before)."

I've got a Plasma III for the top plugs that I've been very happy with for the last 500+ hours. Wire it up just like the manual says and you'll have zero issues. Mine has the Hall effect module.

When Slick came out with their service bulletin a couple of years ago I swapped out that mag for an eMag and have been extremely happy with that ignition system, also with zero issues over the last 150+ hours. To be fair, I had zero issues with the Slick mag for 350+ hours.

Just went flying the other day after completing the annual inspection, 97 degrees OAT, and all CHT's were no hotter than 355. I was also leaning during the climb at 120 kts. Slowed her to 90 kts and highest temperature was 375 on my IO360. At 23/23, anywhere from 5.5k to 9.5k, I get 170 kts TAS burning 7.9 GPH LOP. When I had the Slick mag, I'd burn 8.5 GPH LOP on my IO360 with a Hartzell CS prop.

Pros of eMag:
Super easy to time (compared to a regular mag and/or the Plasma)
No internal plastic parts (that I know of)
Weight savings over a mag
More choice of plugs and consequently much cheaper
21st century product :D

Cons:
Can't think of any

As far as research, like others have mentioned, I do like the availability and variety of options and responses found on VAF. I'm not into reinventing the wheel but somewhere along the line you have to chose what's right for your aircraft.
 
Pretty sure eMag timing is at TDC or 1-6 degrees after TC.

Yes you are correct, it was a typo on my part. My Pmag is timed 4 degrees after TC. Slick on the right side is 25 degrees as is standard. Previous post has been fixed.

I'm betting if a guy timed a Pmag at 25 degrees like a traditional mag things really would not go good!
 
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Many of the posters on this forum are very, very new at airplane building/maintenance and new to this forum. The search that some think is so “simple” for them is impaired for the newbie by the “you don’t know what you don’t know” concept, not to mention cumbersome limitations imposed by vBulletin’s arcane search engine. It would seem reasonable to hope that if an “expert” would take the time to read the post and type the response “do a search”, maybe he could help out a less knowledgeable poster and take a little extra time and provide a link. Otherwise…maybe just skip over the post altogether….always an option.

Seems to be a lot of discussion in this thread concerning "forum etiquette". Moderators are happy with it, so let me drop some more "advanced" forum knowledge for those who are new. Consider it a public service:

Forums like this have been around for decades, and if there is a singular cardinal rule across all of them it is to "do a search" before posting a new thread. I did not make this rule up - it just "is". Now, for the true forum newbie, understand that unlike the polite and respectful response I gave earlier in this thread, MANY other forums would be very, very harsh for committing this faux pas. In many cases the "...do a search..." language would be followed up with unflattering opinions about your IQ, your manhood, or numerous emoji characters or memes reflecting the same. We are fortunate to live in a world with a civilized forum such as VAF. Here is an example from another, also polite and civil aviation forum response from just today:

Not that new, we already talked it to death here:

...Please search before putting up a new thread.

It should be noted that the above quote was from a forum moderator interested in keeping his forum content organized and useable as a technical reference.

For the forum newbie - use this forum as a technical library, not an ongoing stream of consciousness journal like farcebook. This forum flourishes when NEW info is added and the existing is archived, organized and available for future users. Understand that its not that people are being lazy when they tell a newbie to "do a search", it is simply the fact that there is such a huge quantity of archived material related to the question that the reader would be dealt a misservice with one or two direct responses. In the case of this thread, there is quite literally HOURS of material available at the firgertips of the requestor. Who am I to try parse out what I think is important to the reader? Its like driving to the library, walking up to the check out counter and asking the librarian "...show me how to make pottery..." - All the while ignoring the volumes of information sitting within reach on the shelf.

That is my public service for the thread. To those who will heed my words and benefit from my years on various forums - you're welcome. For those of you who feel I did not do enough to help out the new guy - It's my burden try to live with the fact that I did not live up to your expectations. No hard feelings either way.
 
Over the years, I’ve owned three different vBulletin licenses have have had three forums - two specialty-oriented and one general public. I appreciate hearing your opinion, have heard it before, but disagree with it. I’d explain further but there’s no need and I don’t want to appear rude. As you say…no hard feelings and I’ll just leave it at that.
 
The world would be pretty dull if we all shared the same opinion. As long as we all agree that opinions are equally "valid" from a certain perspective, we can work it all out.
 
I just bought a pair of PMags.... Yet to fly with them. I have been following EI on airplanes for decades. I remember the early Jeff Rose EI Electroair. The original was crude by todays standards. Electroair is a different company. Then came Lightspeed then EMAG.... now Surefly

The comments above are very good and agree with #2 post. There is one and only one EI that is self powered. PMAG (they don't even make the EMAG anymore). The ease of installation and set up can't be beat.

All EI do similar things, all of them. They all, verses standard magnetos, have more energy and can spark across a larger electrode gap, have advanced timing verses fixed timing, and no "points", triggering is by hall effect typically. Most Electronic ignitions use automotive plugs, because you can gap them wider than massive electrode aircraft plugs, and they are much less expensive; however you can run aircraft plugs if you want with your EI. However aircraft plugs can not be gapped very wide.

There are fancy claims of more spark power by one brand or another of EI. These claims are likely true. Does it matter? All of them are high energy compared to a regular magneto There are only so many volts you can use. Also the ability to fiddle with timing and monitor advance in cockpit is nice but not needed for daily flyer. The PMAG does not come with this ability for inflight adjustment, BUT you can make changes on the ground. Also there is a communication port on the PMAG that works with "EI Commander", an aftermarket cockpit display to monitor and tweak timing. For me I can tweak the PMAG on the ground and leave it alone. No need to fiddle with it all the times and don't care to monitor advance all the time.

The Lightspeed III is different and stands alone as the only CDI ignition. Capacitance Discharge Ignitions in general have advantage of ability to handle extremely high RPM and longer duration spark. In a slow turning aircraft engines this advantage may not be great. If racing at RENO it might be that tiny edge? Most Electronic ignitions on airplanes (and cars) are distributor-less Inductive discharge ignitions.

Customer service. PMAG is known for great service and Brad will talk to you. He is a wealth of knowledge. The PMAG has been around for 20 years. As I said I just bought a set. I was concerned looking at all the post 15 years ago. There were a few issues and 3 service letters (you can look them up on EMAG's website). ALL of this has been sorted out and addressed. Lose magnets fixed by new design. Losing timing reference at start up, due to going into setup mode. This was random, did not affect everyone and may have been Pilot induced, but it was fixed by firmware. Ross at SDS is on these forums. Klaus at LightSpeed has a reputation. Don't know about SureFly, FlyEFI or Electroair.

The big difference is PMAG's are driven off the accessory case like a Magneto. There are NO POINTS or DISTRIBUTOR ROTOR... The shaft drives the trigger magnet and "alternator" to power PMAG. It has to deal with heat and vibration. For that reason it needs a cooling tube and you have to remove PMAG at 12mo condition inspections or every 100 hours per manufactures recommendation, to check lateral play of drive shaft. Not a big deal.

With the other systems you have to drill your ring gear "flywheel" and plant magnets and attach hall effect sensor on case. It is more work but no wear parts like shaft bearings on PMAG. (Note Lightspeed and Electroair offer Triggers that mount in the magneto holes and don't require drilling the ring gear flywheel.)

PMAG is easy to install and it is all self contained. All these other systems, requires a lot more wiring, coils and controller. mounted in different locations. More connections are possible failure points. However nothing is 100% perfect, even traditions Magnetos can and do fail from time to time. That is why we have TWO of them.

Last is cost. They all cost a lot. In Round Numbers they all cost north of $3500 for dual system. Most are fairly complete but with PMAG you do need gears. Those would normally come off your Magneto you removed. If you have to buy them outright it adds another $450 for two gears. On the OTHER ignitions you will need to spend significant money putting in a redundant electrical system, wiring, battery, switches.... so that will even it out. Redundant electrical systems always adds weight.

Every ignition on the market will "work" but you have to weigh all the factors. PMAG is the ONLY self powered EI. All others require redundant electrical system. There are two EI that also can be part of a EFI (Electronic Fuel Injection), SDS and FLyEFI.

Not a factor for your Experimental Amateur built RV, but some brands aircraft EI have certified STC versions, SureFly and Electroair come to mind. I believe PMAG is working on this. I recall the STC requires you retain one Standard Magneto. BTW that is always an option even for Experimental Kit builder. Go with one Electronic ignition and keep standard Mag, verses dual EI and redundant electrical system.

Would I recommend PMAG? Yes for me. However your mileage may very.... literally. All EI will as I said provide a bigger, fatter hotter spark and advance timing alt lower power adding efficiency. How much? Cafe' Foundation did some flight test and I recall 4% to 6% but there are too many variables. For one you have to be under 75% power. Also how you LEAN is key. With EI you can tend to get into the LOP operations, for more savings. It is hard to say how much you will save. It is like driving a car. If you do jackrabbit starts from the stop light and race to the next stoplight, speed verses accelerate slowly, coast to stops and do the speed limit. Same car way different mileage. Is one EI better than another for performance? Don't know, but any EI (even just one and using a regular magneto) is the big jump. I do recall the SECOND EI does not double your efficiency, but it may allow easier and smoother LOP operations. If all you do is fly around at SEA LEVEL at WOT (Wide Open Throttle) a fixed timing regular Magneto will be fine.
 
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Pretty sure eMag timing is at TDC or 1-6 degrees after TC.
That is pretty much right. The total max advance is 9 degrees. So for a Lycoming it will be 25 deg BTDC after start, and Max advance is 34 Deg (somewhere around 65% power or less).

Yes you set it up at zero, TDC. Internally it advances to 25 deg BTC after engine start. If you NEED less or more base line (100% power advance,) you add or subtract from TDC. Some aircraft engines are not 25 BTDC. EX: You want 23 BTDC, you set up 2 degree past TDC. Then your max advance would be 32 degree.
 
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I just bought a pair of PMags.... Yet to fly with them. I have been following EI on airplanes for decades. I remember the early Jeff Rose EI Electroair. The original was crude by todays standards. Electroair is a different company. Then came Lightspeed then EMAG.... now Surefly

<<SNIP, SNIP>>

However aircraft plugs can not be gapped very wide.

Lots of good info deleted but one (minor) slightly different view.

Been running "Jeff Rose" ignition since 2002. Just changed it out for a second PMAG (because the plastic nipple on the MAP sensor from 25 years ago finally broke.)

During the 20 years of use, I was able to use aircraft plugs gapped at (I think) .035" as opposed to .019-.022 (I think) that is the traditional gap. The plugs I typically used were REM37BY's. Tried some AC Delco ??486's as well for a short period.
 
I am not sure that Pmags are anymore reliable than mags. My hanger neighbor just had his Pmag die and had to send it in for repair at well less than 500 hours. Similar stories out there - search for bearing failures.
Your buddy and heard of others is not super scientific, but yes some have failed in the 20 years they have been flying. How long has SDS CPI-2 been flying? 3 yrs. How many revisions has Ross made? Pretty common development and I agree it is a great ignition from all I see. As far as PMAG there is NOT a bunch out there failing on regular occasion. I would not throw out PMAG's are not reliable with out data and statistics. ALL ignitions can and do fail. Bearings. I talked to Brad. In my opinion there should NEVER be "bearing failures", but there is wear. I say NEVER if you are doing the continued airworthiness inspection, you check the lateral play of drive shaft every annual. If no play good to go. How long do they last before bearing change? Depends on engine, prop, how you fly. Some early PMAGS are still flying with original bearings but don't have hard hours. However it is a wear item, granted. Just check it at annual (condition inspection).


high CHTs caused by overly agressive (aggressive) timing maps that cannot be adjusted for the operating conditions.
Aggressive? The PMAG has one of the more conservative advance MAP and can be tweaked. As already stated if you don't have a CHT issue now with a magneto it is unlikely to be created with a PMAG. You can set the timing baseline timing, and it is fixed at the baseline advance you set. You can adjust the the advance starting early or later. TOTAL advance does not start until under 75%. Total advance is a fairly conservative 9 degrees. Some other brands will advance 15 degrees.

However, it has drawbacks too, such as losing that b/u if the RPMs fall below around 800 and won't re energize.
I have a constant speed Hartzell and RPM never get's so low the PMAG would cut out (around 800 or 900 RPM. Let me rephrase RPM would not get so slow and cause the PMAG to not be self sustaining, until rolling out after landing.

Thank about pulling the throttle back on final and then needing to go around. Small SLA batteries cost $25 and are very easy to install. The SDS system even has built in circuitry for charging and using it; Just wire the small battery to their box. Couldn't be easier. You can also do one mag and one EI, then no worries about power source.
All true but easier? Drilling ring gear flywheel wiring is not as simple as PMAG drops in the Mag hole and has Power, P-Lead (ground), Ground, Tachometer signal if you want. There is a COM channel if you want to monitor the ignition in cockpit. Redundant electrical is not something to take lightly. Ross has built in an option for backup battery. That is cool. However a Dimond DA62 Twin Engine planes with electrically dependent diesel engines, cost $1.5 million, have had more than one off field landing due to loss of power from electrical failure. To be fair to Dimond I know one of the accidents was Pilot induced. However this plane has LOTS of electrical redundancy yet several have lost electrical power which caused loss of power. Don't discount the internal self powered aspect of the PMAG.

Not trying to push my bias here, just trying to drive you to do the research. You have many choices today, however, Caveat Emptor still applies. Larry
SDS CPI-II is pretty good. Yes do your research.
 
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Mags have higher spark energy than most EI’s

Energy_graph_small.jpg


Duration_graph_small.jpg


https://www.flyefii.com/products/efii-systems/ignition-comparison/
 
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I just bought a pair of PMags.... Yet to fly with them. I have been following EI on airplanes for decades. I remember the early Jeff Rose EI Electroair. The original was crude by todays standards. Electroair is a different company. Then came Lightspeed then EMAG.... now Surefly

<<SNIP, SNIP>>

However aircraft plugs can not be gapped very wide.

Lots of good info deleted but one (minor) slightly different view.

Been running "Jeff Rose" ignition since 2002. Just changed it out for a second PMAG (because the plastic nipple on the MAP sensor from 25 years ago finally broke.)

During the 20 years of use, I was able to use aircraft plugs gapped at (I think) .035" as opposed to .019-.022 (I think) that is the traditional gap. The plugs I typically used were REM37BY's. Tried some AC Delco ??486's as well for a short period.

I could in fact tell the difference in RPM improvement between magneto->Pmag->ElectroAir (Jeff Rose). In that order.
 

Walt interesting. I have to research this more, but two things....

1) Consider the source of this data? I would like to know how this data was developed, measured, conditions... That is all I am saying. This is a sales promotion. It could be great data. I think it's a bit self serving and suspect, no offense to EFII.

2) All EI can run an Automotive plug gapped at 0.035 inch (fire under pressure different than ambient), including PMAG. The reason aircraft plugs have small gaps (smaller spark, subject to fouling) is not because they want to. The Magneto can not produce enough EV to fire a larger gap. The other part of this is there is ONLY so much spark energy you can use. Once it has jumped (in fraction of second), it's over, combustion happens. Extra voltage is not a bad thing, but it is not the be all end all.

I'll research this claim but a PMAG and all EI's improves smoothness, efficiency, easier starting, and easier to achieve LOP operation, verses a standard Magneto. I am not promoting any EI over any other. Standard Magnetos are fixed timing but that is OK for the way many people fly

The standard magneto is pretty good performance, good reliability. There is the fairly extensive 500 hour maintenance thing with some magnetos, but that is part of continued airworthiness, like PMAG bearing check every annual. However the bearing check takes 10 seconds and is only an inspection.

Magnetos (not electronic ignition) do one thing no other EI does (except PMAG), they are self powered. Being 100% totally independent of electrical system has some charm.
 

While the mag numbers seem to be in line with what I would expect, I feel this is the wrong parameter to be comparing. From what I have read, 20 Mj is more than enough energy for most every situation and typical of today's auto OEMs. The better parameter to follow for performance is Voltage. It is voltage that allows the spark to jump the gap and the amount required increases with various different obstacles to jumping that gap, such as low ambient pressure, lean mixtures, combustion chamber turbulence, etc. The more volts produced, the greater the ability for the spark to jump the gap.

This is pretty much old science. Once we started leaning out engines in the 70's (beginning of fuel efficiency era), we learned that more volts were required to consistently jump the gap with the leaner mixtures and the whole world moved to high energy ignition, which was really high voltage ignition. The voltage induced was increased at the expense of current or joules produced. We learned that a higher ignition voltage would better insure consistent sparks across more challenging environments, namely leaner mixtures in this example. We also learned that large amounts of current or joules were not required to light the charge when the voltage went up.

I would argue that ANY of the EI systems are vastly superior to the mag due to the higher voltages that they produce. Remember that mags have to jump TWO gaps instead of one like EI does, creating even more problems with their low voltage output. Also evidenced by the need for pressurized mags for high altitude (pressure reduces the voltage required to jump the rotor to distributor gap) Once the auto world moved away from distributors, the ignition voltages dropped from the 45-55 Kv of that interim era, as they now only had to jump one gap and the lower voltage reduced the risk of wire jumping due to failing wires.

Larry
 
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I would like to thank the OP, Jim, for having this thread (which, as an aside, he could close anytime by himself, being the OP ;)).

We are evaluating resparking the -8 from mags to any better ignition system. My -6.9 sports a dual LSE, which I’m very happy with. The back-up battery is a small and light Yuasa 12V/2300mAh, recharged via a diode during normal ops…
The problem with the LSE, and some other EISs, is the amount of work for the install. Coils, microprocessors, back-up battery, trigger sensor(s).
Installing the mentioned P-Mags is almost, save for 2 power leads and CBs, a drop-in affair. From the reads here, and based on the experience from other people on my field, the only negative is the recurrent 100h inspection (my LSE has been running since 2015, close to 1‘500 hours „automatically“, as in nil action but biennial back-up battery replacement).

In short, though the subject has been treated and debated a few times already, reading the latest informations here, makes this thread worthwhile, thanks Jim.
 
I would like to thank the OP, Jim, for having this thread (which, as an aside, he could close anytime by himself, being the OP ;)).

In short, though the subject has been treated and debated a few times already, reading the latest informations here, makes this thread worthwhile, thanks Jim.

First, thanks to all who contributed to this post - even the person who criticized me as being disrespectful for starting it. Second, as the “OP” I had no idea that I could close it and am extremely grateful for the information people have shared - therefore glad I didn’t.

I’m still waiting on Popular Grove to tell me about my engine tear down inspection which is what prompted to consider changing to PMags. Hopefully I will soon see true progress and get the engine back to Myers at OSH. This has been a challenging year with the prop strike at Airventure, followed by minor medical issues, and helping a friend sell his RV9A. Someday, I’m told my airplane will be ready for pickup. I can hardly wait!
 
Great post but WHY close it?
Thread 3 mos old has generated some of the most interesting post in last few days.

Most threads are left open indefinitely, so they can be commented on. It will be a new topic to others years down the road. Just because it was discussed before does not make is less valuable.
 
... like PMAG bearing check every annual. However the bearing check takes 10 seconds and is only an inspection.

Next condition inspection, how about I fly to you and let you show me how to do that 10 second inspection. It has always taken me a lot longer than that to remove the pMags, check for bearing runout (whatever that means without a published spec) and then reinstall and retime. Guess I'm just really slow.
 
6 Cylinder PMags N810RK

I have dual the 6 cylinder (200 series) PMags on my Barrett 540-X engine in my RV10 (290hp). I am quite happy with them. No backup battery is required. Emag Air did a lot of testing with different ignition timing curves. The two places that matter are Takeoff Power and Cruise Power. The PMags have a maximum advance of 9 degrees, so at cruise power I am timed at 34 degrees before TDC. Testing proved that there was no real advantage running more advance than that and more advance moved you closer to detonation. I also got my injectors tuned for my engine by Don Rivera at Airflow Performance. It was very worthwhile. Currently I am running 21 inches and 2,300 rpm at cruise at 10.5 gal/hr. (55% power LOP). That gets me 175 knots true at 10,000 ft. and 16 nm/gal in still air. The spark plugs are cheap. I use the iridium ones and clean the lower ones every oil change (50 hrs.) and all of them every 100 hours. That is probably more often than necessary, but I never have any issues with ignition checks. I don't like having problems on road trips.
I see a lot of pilots talking about high CHT's with electronic ignition. If my CHT'S went up when I installed the PMags, it was so little I never noticed it. I am usually running around 390F climbing out on 100F days and running about 370F in cruise. I lean a little in climb starting at about 6,000 ft and watch my CHT's closely. I run LOP in cruise.
I made some cooling shrouds for the front of the PMags out of Carbon Fiber. They wrap half way around the PMag and have a 1" blast tube hooked to them. They were easy to make and make the blast tubes more effective. I used the rounded end of a 2X6 for a mold and tapered it just a little to make the shroud easier to get off the mold.
 
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Next condition inspection, how about I fly to you and let you show me how to do that 10 second inspection. It has always taken me a lot longer than that to remove the pMags, check for bearing runout (whatever that means without a published spec) and then reinstall and retime. Guess I'm just really slow.
Relax my friend. Obviously I thought people knew, you have to remove PMAGS from accessory case to inspect. The WIGGLE test for bearing play is 10 seconds. Yes to pull it off, wiggle, put it back, and reset timing, 30 mins? Times 2, an hour? is this a big deal? No. Yes it is done during 12 month condition inspection, cowl is off, oil change, compression checked, plugs replaced and PMAG wiggle test. it is all part of maintenance (fun). Sorry you misunderstood and triggered. Apologize. Everything is OK. You can fly anywhere you want, but of course always be safe.

BTW other EI require periodic inspection of wiring, connections, magnets, sensors... granted may be less time consuming, but it is not nothing. PMAG is all in one unit, not a lot to check except for the high tension leads (spark plug wires), which applies to all EI systems.

Not recommending you or anyone do this, but some don't inspect bearing play routinely. Some PMAGS have been in service 1500 hours with original bearings. The EI Commander (optional aftermarket cockpit monitor) uses PMAG data COM port of both PMAGS, It looks at DELTA (difference) between L & R timing. This is an indication of bearing play. The operators who use this monitor justify not doing inspections of bearing play with the monitor. Again not recommending just what some do.
 
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As an add on, regarding the frequency of inspection for the P-Mag, the manual states: Annual or 100 Hr. Inspection (whichever comes first).
 
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