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E mag P mag reliability

I posted an image in post 22 here where Don Stiver logged the advance numbers being reported by his EI Commander while running the equivalent of the A curve.

He found the minimum advance at high power to be 28?. So if you mechanically time your Pmag to 1? ATDC the effective timing would be 27? at the same power levels if Don's numbers are accurate and I believe they are based on my own testing.

So let's see if I got this right:

On the "A" curve, mechanically setting the timing after TDC reduces the theoretical timing (Max and Min) by an equivalent amount. Say from 28 to 27.

On the "A" curve, mechanically setting the timing before TDC increases the theoretical timing (Max and Min) by an equivalent amount. Say from 28 to 29.

:cool:
 
So let's see if I got this right:

On the "A" curve, mechanically setting the timing after TDC reduces the theoretical timing (Max and Min) by an equivalent amount. Say from 28 to 27.

On the "A" curve, mechanically setting the timing before TDC increases the theoretical timing (Max and Min) by an equivalent amount. Say from 28 to 29.

:cool:

Yep, BTDC mechanical shift effectively advances the whole mess by whatever angle you set before TDC.

An ATDC mechanical shift effectively retards it in the same manner.

It has been recommended in the past to time the Pmag a few degrees ATDC to allow for lightweight props with little inertia during starting. The need for this has been eliminated with V40 firmware as the Pmag automatically does this at low RPM during start.
Some have also recommended doing this for those with high compression pistons and/or those that don't want as much advance as the A curve provides but don't want to fool around with the EICAD software or purchase an EI Commander.
 
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Can we have a P-mag discussion without it turning into an SDS ad? That is why I stopped commenting on comparison threads...


As soon as the other ignition suppliers get their act together and stop stuffing an inappropriate curve down the consumers throats, sure. Until then, I hope to educate as many people as I can that there is a more appropriate option.
 
Let's not forget, one of the main advantages and attraction of the P-Mag is the fact that they are self powered (after the start) and does not require a more complex, heavier and more expensive electrical system for back up power. Also the installation seem to be far easier than most if not all other E-Ignition systems, this is specially true for an already flying aircraft where you deal only with the hot side of the engine and not much gets routed to the cold side.
My two P-mag ran without any issues and I saw about a gallon/hour of fuel saving running LOP with the standard curve. I had the EICommander but end up sticking to the standard A curve.
For the test power switch, I had a mini toggle switch for the run up area which would kill the ship's power to each of the P-Mag and also hooked a warning light that would be on if/when the ship's power was off. This was as a safety measure just in case I hadaccidently flipped the switch to the off position.
 
As soon as the other ignition suppliers get their act together and stop stuffing an inappropriate curve down the consumers throats, sure. Until then, I hope to educate as many people as I can that there is a more appropriate option.

Just like an EFIS, the P-mags can be tuned for your application.

However, the stock A configuration is more than adequate for most stock parallel valve engines.

If the A configuration was as bad as some argue, there would be melted engines all over the place.
 
...Just like an EFIS, the P-mags can be tuned for your application..

No, they can't.

...However, the stock A configuration is more than adequate for most stock parallel valve engines..

No, it's not.

...If the A configuration was as bad as some argue, there would be melted engines all over the place.

Yes, hyperbole abounds, but there is significant and compelling evidence that even the A curve is "sub-optimal" and does indeed result in unnecessary CHT excursions.

Your own advice to alter timing mechanically and yes, even the success of your EI Commander product hinges on the very shortcomings of this ignition. After all, if Pmag adopted the features of CPI, You'd have no product! Pmag is a "good" product but will never be "great" until it changes to accommodate an increasingly intelligent customer base. We've already seen one previously stagnant EI/EFI supplier rise to the challenge of SDS and adopt many of Ross' innovations - I would only hope the others do likewise.
 
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Michael, I respectfully disagree.

There will always be a market for products like what Ross puts out because there is always someone who wants to tune their engine for the last bit of power.

However, I have come to the realization that most people want a simple and reliable product that they can install and forget, which is pretty much what the P-mags are.

While the P-mag curve isn't optimal, it works for most engine configurations. Some people don't have any CHT issues and others do. My old engine with a stock Van's cowl ran cool but my current engine with an aftermarket cowl runs warmer. It could be the ignition, compression ratio, cowl, engine size and/or something else. Being able to adjust the timing is just another tool to get a desired outcome.

The problem with an ignition that allows someone to change the complete curve is that most people don't have a clue how to do it and doing it in flight is less than ideal.

I will take the reliability and simplicity of something like the P-mag over a multi component ignition system any day. Others have different risk tolerance, and that is what is great about E-AB aircraft.
 
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Back to the reliablity issue Mr. Chzech mentions. I'm not sure what the reliablity is of the P-Mag, but from most others seems ok. What I do know is that they produce one of the best sparks with good timing. They are also the only Mags I know of that do this and will continue to produce a spark if the battery system fails. With dual P-Mags and testing each everytime you fly the reliablity question should not cause as loss of function problem on a given flight. You might lose one but very unlikely you lose both. The reliablity then becomes a customer satisfaction issue. If one of my dual P-Mags fails and EMAG has great customer service then I'm going to be a happy camper.... well I hope to be camping hapily with my RV some time in the future. :)
 
...I have come to the realization that most people want a simple and reliable product that they can install and forget, which is pretty much what the P-mags are.

The above is perfectly valid as a marketing decision point. And the supplier will have to live with that decision.

...While the P-mag curve isn't optimal, it works for most engine configurations. Some people don't have any CHT issues and others do...

This is an engineering assessment. The curve is not optimal. My point is that there is a product that is better from an engine performance standpoint. One can choose to minimize the importance of this fact, but it will not go away until the "sub optimal" candidate improves. This is not personal, just the way of the world.
 
p-Mags

For this non-tinkerer, I think p-Mags are great.
- easy installation
- auto plugs (cost less to replace all 8 every annual than replace one aviation plug)
- easy starts
- smooth idle
- better economy (about 1/2 gal per hour in my case)
- easy timing
- self powering at cruise
- coming up on 100 hours trouble free operation. (not significant yet)
- lighter weight
- great customer service

Can't think of any cons. Haven't had any CHT issues.
YMMV
Just a happy customer!
 
IMHO; at some point good enough is good enough or nobody would ever finish building anything. For the vast majority of people good enough is what they need to complete their particular mission. For others chasing perfection is how they enjoy their particular mission. That doesn't mean either one is wrong.

Most people, myself included, are not interested in the chase of perfection especially if it means an increase in complexity. Remember, by chasing perfection you can accidentally wind up with "Paralysis by analysis".

Go fly!

 
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Tractor magnetos?

I bought an 8 equipped with one tractor mag,and one Lightspeed system firing auto plugs.After about 60 hours the Lightspeed got an intermittent miss.After reading many comments about various ignition systems,and how great Pmags are,I put one on.After35hours,once again there was an intermittent miss that was narrowed down to the Pmag.Sent it back,and was told it had internal screws falling out from lack of Locktite.Twice the tractor mag got me back on the ground safely when the modern electronic ignitions let me down.In 1500hours of flying properly maintained tractor mag equipped aircraft they have always gotten me home.Modern electronic ignitions? Not so much.Just how it's worked out for me.
 
There are literally 100's of posts about pmags on the Vans forums, some good and some not so good. You should do a search and get all the information available.
 
For this non-tinkerer, I think p-Mags are great.
- easy installation
- auto plugs (cost less to replace all 8 every annual than replace one aviation plug)
- easy starts
- smooth idle
- better economy (about 1/2 gal per hour in my case)
- easy timing
- self powering at cruise
- coming up on 100 hours trouble free operation. (not significant yet)
- lighter weight
- great customer service

Can't think of any cons. Haven't had any CHT issues.
YMMV
Just a happy customer!

My experience and saticefaction mirror the above. 160-165kts TAS at 8-12000' burning 7-7.5gph. Low CHTs. Dual pmags V40 now but no issues for all 150+hrs so far. Precision FI also contributes to the economy and easy starting. I would do the same again. Factory response to my questions have been quick and thorough. Bevan
 
The op was to Pmag reliability, I have not seen anyone post having problems with a Pmag, yet I know they are out there. I had 5 failures before removing them, including 3 bearing failures, two electronic failures and two in flight shut downs. The last failure was not able to be reproduced on the bench at Emagair, yet I know for certainty it quit cold and left me over the Tehachapi's on one ignition, and it was not an install or wiring issue.
These were current production 114 Pmags on a 0-360 A1A that previously flew 700 hrs on 2 Slicks, and 100 hrs with an ElectroAir Mag timing hole sensor in the RH mag hole with no problems. All the failures were on the RH side, the LH side perfect. This was on a Cozy MK IV, a pusher, and it does appear there are more failures on these airframes than on conventional airframes.
I talked with Brad many times about this, there is an issue not yet understood, possibly related to Lycoming SB 411 (Magneto drive isolation bearing), or just certain engine/prop combinations, that can fail a Pmag in short order. I never once went over 50 hrs on my RH Pmag without a fail, the last one, a loaner from Brad, lasted 4 hours. Most people have good luck with Pmag's, others for reasons not understood do not, but there is a weakness in the design that only reveals on certain installations.
I do not intend to bash Emgair, they were more than fair helping me through this, but they proved completely un-reliable in my experience.
Tim Andres
 
Bill, perhaps the last time I posted a failure here was over 4 years ago, but the last failure was last fall. That's when Brad and I decided it best to not run them on this engine.
And you perhaps mis read my post, the Slicks went 700 hrs on the same engine without failure (or service), the Electroair 100 in the RH hole.
Am I being critical of Pmags? I don't mean to be, but the op was to people's experience with Pmag reliability, what I wrote is my experience with Pmag reliability, no embellishment, no agenda.
Tim Andres
 
Tim, was there another post between your initial one at 5:07 and this last one at 6:27? Your last post seems a bit out of context? Something was deleted?

Anyway, there has been some discussion concerning the merits of a unitized system that the Pmag product offers vs. the "distributed" systems featured on, well, pretty much every other ignition system on the planet...

The only issues I've had were self induced by using non resistor plugs, but during their trip back home to troubleshoot, Brad found some corrosion on one of my boards. This was not a causal factor in the failure (and the board was replaced with a 114 model), but it does bring up a valid caution: if you intend to degrease/clean your engine, make sure the ignitions are removed or covered very well. The case is vented to atmosphere and the brains of the system can and will injest any solvents you spray back there. just be careful.
 
It is reliable for me

I installed pmag about 15 hours ago.

The install was easy and it worked the first time. I replaced the right mag.
I found that on internal power it worked as described which is to die around 850 or fewer rpms. With the external power connected, you can idle lower than that.

I choose to install it because I talked to many other folks in my local area and at osh that have used this device successfully for many years. It does seem to have become much more reliable over the last 5 years or so.

For me part of being reliable is not just that it performs well, but that the folks running the company answer the phone. I actually drover over to their facility and toured the office and their shop where the build the device.

They were frank and honest in regards to past failures and how they mitigated those issues. They also told me about corner cases that have dogged them. I do feel confident with the product. In regards to only using it on the right side, it would not matter to me what brand of EI, I simply don't trust any of them because they collectively don't have enough hours as a community be trusted. That is improving rapidly now for several brands. I also prefer to spread my airplane dollars across a few years as well.

It sucks to be an early adopter and have a failure. It shakes your confidence. That is part of the reason I waited a while before getting an EI.

The Pmag folks have been doing this long enough that I feel that they will not go out of business. I have never heard of them leaving anybody high and dry.

I didn't want screw around with custom maps. I thought about build an EI like Dan did, but ultimately I chickened out. If you want to mess around with your map, you should look else where. If you want it to just work... well, all I can say is that it is working for me.
 
Tim, was there another post between your initial one at 5:07 and this last one at 6:27? Your last post seems a bit out of context? Something was deleted?

Yes, there was a post deleted, just some confusion between me and another thread.
Tim
 
My historical experience:

.Less than 100 hours on Electroair EI on two different airplane's - both had problems and were removed, replaced with magneto.

.500 hours on Lightspeed Plasma III on one side - no problems, ran very well.

.BUT - 4200 hours with dual mags, no mag problems ever.
 
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