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P-Mags

gvgoff99

gvgoff99

Well Known Member
How are people doing with their P-Mag or E-Mags?

I have dual P-Mags and they have been running flawlessly for the past year. I have complied with the Service Bulletins and am getting excellent GPH averages with about 6.5 GPH being average for my X-country flights at 2500 RPM in a 160HP Lyc O320 with two blade Catto.

I have not heard of any recent problems has anyone else?
 
P Mags

What little time I have experienced with my dual P Mags is wonderful. My Rv-4 is presently being refurbished by the capabable gents @ Hotel Whiskey Aviation. I thought I had a new engine relplacement with the P Mags. (0-320 160hp) I dread the thought of going back to regular mags. The engine acts completely different....instant response, better fuel consumption....

.....it was like the first time I experienced cruise control in an automobile....I ain't going back fellows....

Just my two cents...

Cheers,

Deal Fair
RV-4 (N34CB) Undergoing TLC @ HWA
George West, TX
 
Had issues early on

But have been flawless since the latest upgrades

Frank emag/Pmag
 
Are you guys using aircraft spark plugs or auto plugs? Any radio noise with the auto plugs?

Mitch Garner
RV-4 flying
PL-4 flying
RV-12 started
 
Mitch,

Around 250 trouble free hours when I had my taxi incident in June.

I couldn't be happier!

Those who have kept up with the service builletins haven't had problems.

I'm running eight auto plugs and have no radio problems of any kind.

Heck, your car runs auto plugs and you don't have problems there do you?

BTW, you might want to check out our Electronic Ignition Commander control moduel for E/P-mags.
 
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Auto

plugs and aurogas, with or without Ethanol..run lean of peak most of the time..

Warning I have a modified fuel system that resists vapour lock with just about any fuel..Your milage may vary

Frank
 
Looking to Replace the Mags

On my new purchase RV4, I am looking into different EI's to replace the two mags. On my -7 I had dual Lightspeed Plasma II and they worked great. E & P mags were not around when I went with the Lightspeed.

Can anyone make a comparisson between the two especially in a retrofit situation? Are most of you going with one P & one E mag? What if any real benefit is there with going dual P mags...the website is not really clear on that.

Thanks
 
It's been kinda quiet on the P-mag front lately... nice! I do believe the issues are getting ironed out.

I'm at 580 hours on mine; had plenty of problems for the first 225 or so hours with multiple trips back to the factory on both units. But now, they appear to have found their happy place, 300+ hours with no troubles. All Service Bulletins have been complied with. I really like these things; it starts fast, runs smooth, decreased fuel burn, never had fouled plug issues during a runup. Compare that to the junk rental ships I used to fly with Slick mags, had to burn off fouled plugs at every other runup.

I'm using 8 NGK spark plugs; I replaced the last set after 220 hours, no lead balls and just $20 to replace all 8. Sweeeet.
 
Pmag vs Emag

The Pmag is self powered so if your electrical system goes TU you can kill everything and still run the engine.

The engine runs very smoothly on one P/Emag so the benefit to having two Pmags is marginal.

Then again the extra cost is not huge either..At least in airplane money...:)

Frank
 
Working good

I haven't had any problems since the updates were performed and I found the ground problem. I'm running two P mags but used to have an E and P. Two P's is overkill in my opinion.

I'm running auto plugs. I pull a couple of them every other oil change to check. They are very clean. At the annual (okay, condition inspection) I replace them, regardless of condition. At a buck 74 each, it's not worth not replacing them. I carry a couple as spares.

I would recommend when wiring these, to avoid any connectors and insure your connections. I was having a tach reading problem and finally traced it to a faston connector that was in-line. Soldered the wires together and the problem was solved. Also added blast tubes since I fly in the hottest conditions most will ever experience.
 
NKG autoplugs. No interference. I will replace all 8 in the next few days. I am doing the first annual.

I am on dual P-mag, but one E one P would be fine also. They just work, unlike so many magnetos.
 
Read it

Garage Guy said:
What about this recent problem... doesn't seem to really be resolved yet:
http://www.vansairforce.com/community/showthread.php?t=45501

--Paul
Click to expand...

Read the entire post. He had NOT sent them in for the updates.

"I had not send them in for the recall because they were made and serviced before the dates in the bulletin. Maybe this was a mistake. I will update this thread when I know more."

Again, no known problems since the updates. Could be some out there but nothing reported.
 
I agree

There were a number of E/P mags that were not covered by the SB..Mine were in that group. I sent them in and had them upgraded anyway as brad was very happy to do them for free just like any of the others.

I think the 1 or 2 cases where there were problems we were they had not been upgraded.

As others have said, the motor starts like a car and runs very efficiently..I get 160kts TAS at 12k or above at 7.3 GPH running 100LL.

I did not notice what the TAS running the same on autofuel with 10% etoh..In theory it should be slower but I didn't check on my most recent long X country.

Certainly at over a buck a gallon less for mogas its certainly not so slow that its not worth using.

Frank
 
No Problems with the Mags

About 300 hours on the airplane using auto plugs.
Every time I replace the plugs they still look new. They're so cheap I figure once I have them out I should replace them anyway.
 
Capflyer said:
On my new purchase RV4, I am looking into different EI's to replace the two mags. On my -7 I had dual Lightspeed Plasma II and they worked great. E & P mags were not around when I went with the Lightspeed.

Can anyone make a comparisson between the two especially in a retrofit situation? Are most of you going with one P & one E mag? What if any real benefit is there with going dual P mags...the website is not really clear on that.

Thanks
Click to expand...

Mike,

Replacing traditional mags with E/P-mags is very easy. There is no brain box for these like with your Lightspeeds. You can even use the mag wires you all ready have. Of course each E/P-mag will need its own power lead and fuse/breaker.

Other than that, they plug in just like a regular mag.

You can down load the manual from the E-mag site and see for yourself.

As for two P-mags or one E & one P-mag, I put in two P-mags because when I bought them years ago, the price difference was very small. If I were buying today, I might do one of each, then again, maybe not.

Either way, they are simply a good product.

If you are nervous, buy one, and install it. I guarantee you will be back for a second one.
 
I agree!
I have flown 3 different generations of e-mag's and P-mag's with 100's of hours on each. I only had one problem, that involved the SB and was promptly fixed by Emag.
I'm currently running 2 P-mag's with auto plugs (NGK) and love them. The engine stars like a car hot or cold. It runs smoother. Installation and maintenence are a piece of cake. Plus the Emag guy's are great and provide exception service.

Doug Crumrine
RV-8 N169FS
 
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Glad I asked!

I also have not had any problem since complying with the Sept 2008 SB on the Mags. I like the ease of starting and the economy.

I did a 3-hour X-country leg last week at 8000+' density altitude at 2500 RPM. I always lean aggressively when in level flight and got 6 GPH (fill up was 18 gal for the 3hrs and 2 minutes of flight time.) I usually don't check the GPH but the math was too easy, even for me, for this flight. I started in Durango, CO and flew to Texas so that is cheating a little bit on the initial climb.

Does anyone else keep GPH for the E-Mags or P-mags? There has to be numbers out there that would be a better bit of scientific information than my one bit of data.;)
 
RV7Guy said:
Read the entire post. He had NOT sent them in for the updates.

"I had not send them in for the recall because they were made and serviced before the dates in the bulletin. Maybe this was a mistake. I will update this thread when I know more."

Again, no known problems since the updates. Could be some out there but nothing reported.
Click to expand...

Well, I don't want to be the only guy who experienced a problem, but on 3 separate occasions I've started my -7A and only one P-mag was operating. I had sent them in late last year for the latest firmware upgrade. They've got version 29 written on each one. I called Emagair and Brad said "hmm, maybe the firmware didn't get upgraded". WTF?? :eek:

That really bothers me, and I would've hoped he wanted them back ASAP to make sure THEY did their job (at their expense for shipping, too)...but no such luck.

The simple solution is to kill power to the ignition(s) and restart the aircraft. Brad says it sounds like the old problem of too little juice on startup (that was fixed with the latest firmware). Everything operates fine after a restart. I really need to send them in to get checked out.
 
I had One Lose Timing

I had one lose it's timing in flight earlier this year. They couldn't find anything wrong with it. I still run two pmags, but I have postponed my flight to PR until I have 200 flawless hours.

Hans
 
I have 200 flawless hours on my single P-Mag (I also run a 1200 series magneto on the other side). It's a series 113 and has been updated. I love the inexpensive NGK plugs! I simply throw them away every year (despite the fact that they still look new). Unless something better comes along, all of my future aircraft will run the P-Mag ignition.
 
Wow! no negative votes!

I have followed the P-mag story some. It seems like a great concept and I want it to succeed and become so bullet-proof that everyone will have them.

For now, I still think it is prudent to have one each, EI and old-fashioned mag.
I have one Light Speed and one Slick.

The performance gain from the spark timing advance and the spark strength is nearly all achieved with a single EI. Adding the second one brings only modest, if any additional gain. So the reliability gain of two completely different systems seems worth it to me for now. Maybe when my Slick croaks, I'll put a Pmag in.
 
scsmith said:
...The performance gain from the spark timing advance and the spark strength is nearly all achieved with a single EI. Adding the second one brings only modest, if any additional gain. So the reliability gain of two completely different systems seems worth it to me for now. Maybe when my Slick croaks, I'll put a Pmag in.
Click to expand...
FYI - From the guys at E-mag and the experiance of an engine builder I know:

One EI will reduce the average user's fuel burn at the same power setting by about 1 GPH, two will reduce it to 1.5 GPH +/-.

From the engine builder: Having two E/P-mags will increase your HP by 6%. I didn't get the number for one E/P-mag but based on the GPH reduction, I suspect it is probably a 4% gain but I don't really know.
 
How so?

N941WR said:
FYI - From the guys at E-mag and the experiance of an engine builder I know:

One EI will reduce the average user's fuel burn at the same power setting by about 1 GPH, two will reduce it to 1.5 GPH +/-.

From the engine builder: Having two E/P-mags will increase your HP by 6%. I didn't get the number for one E/P-mag but based on the GPH reduction, I suspect it is probably a 4% gain but I don't really know.
Click to expand...


The max power advance of a P/Emag is still 25 degrees like any other mag. So I don't get how you get more power?...Maybe more power for the same fuel burned at high altitude, but this is the same as fuel economy or improved efficiency..Not raw haorse power.

Frank
 
frankh said:
The max power advance of a P/Emag is still 25 degrees like any other mag. So I don't get how you get more power?...Maybe more power for the same fuel burned at high altitude, but this is the same as fuel economy or improved efficiency..Not raw haorse power.

Frank
Click to expand...

Frank,

Take a look at the timing graph on page 20 of the 114 manual, the max advance is 39 degrees and can actually be shifted more than that, if you really want to play with it.
 
I beg to differ

The full power advance is not 39 degrees it's 25!...the max advance happens at very low manifold pressure.....I.e low power. So the full power timing is the same as a mag....so in theory max power is also the same as a mag....confused!!

Frank
 
Frank,

With all due respect - you are incorrect. The advance increases from around 25 degrees to 34 BTDC as the RPM/MP increases. In fact, my observations indicate it will be at maximum by around 1500 RPM.

Richard
 
Really????

Huh I could swear it said it was 25 degrees at full power? Wow I must be getting forgetful!.....that would explain the power increase certainly...hmmmm....


Frank
 
EIS Spark Advance (Timing) = Mechanical Advance + RPM Advance + Vacuum Advance

Here is how Electroair works. I understand E mag to be similar.

The diagram in the Emag manual can be misleading.

More power potentially comes from a longer/stronger spark that leads to more complete combustion and release of energy contained in the fuel.

I may be totally wrong on this, however.
 
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Ahh I see where i got my info

The graph shown does not take into account the effect of manifold pressure (it says so on the notes on the graph).

Back in the text it also says if you disconnect the MP tube, the max advance on the A curve will be 26 degrees. As max power comes with max MP (hopefully ideally close to 29.92" HG on a standard day at sea level) then it stands to reason that full power timing is 26 degrees, at least on the A curve.

if we assume a direct 5 degree shift between the A and B curves (could determine if this was the case from the manual) then the full power timing would be 31 degrees on the B curve.

So I think I'm back to my original assertion that the full power timing is close what a mag provides..At least on the A curve...But not 39 degrees as that only happens at low MP.

Thoughts?

Frank
 
Frank you're right.. they retard as power is increased.. they all do... we can split hairs over 1 degree here.. but pretty much, it's same timing as mag is at (close to) full power.
 
in cockpit programing would be good

frankh said:
The graph shown does not take into account the effect of manifold pressure (it says so on the notes on the graph).

Back in the text it also says if you disconnect the MP tube, the max advance on the A curve will be 26 degrees. As max power comes with max MP (hopefully ideally close to 29.92" HG on a standard day at sea level) then it stands to reason that full power timing is 26 degrees, at least on the A curve.

if we assume a direct 5 degree shift between the A and B curves (could determine if this was the case from the manual) then the full power timing would be 31 degrees on the B curve.

So I think I'm back to my original assertion that the full power timing is close what a mag provides..At least on the A curve...But not 39 degrees as that only happens at low MP.

Thoughts?

Frank
Click to expand...

Frank, I want more spark advance on mine for smoother running lean of peak at higher manifold pressure. The Commander will only do it if I switch timing curves in flight which I don't like. One more thing to manage. I would like to leave the low MP advance where it is and be able to experiment with the advance at higher MP's, or the crossover point where they limit the advance. In other words I think that the pmag timing is too conservative for good LOP operation at lower altitudes. I'm open to ideas.

Hans
 
Tradeoffs....

I have found that I can run more advance and suffer higher CHTs on takeoff with great LOP ops in cruise

or

I can run less advance and have low takeoff CHTs with slightly marginalized cruise LOP ops.

In the winter here in Minne - CHTs are not a prob and I run a custom curve with high advance. I have the control wires in the cockpit and can shift the curve down by running the jumper - this cannot be done in flight, but it gives you options if you need to reduce the CHTs on takeoff.

In the summer, I run a less aggressive curve to allow cooler takeoffs, with some MPG penalty in cruise.

IMO, for most people, curve tweaking is not needed at all, I just like to experiment.

Bill's gizmo makes this easy for those who want ultimate control and is much easier than flying with a notebook on your lap!
 
I agree....

Hans, I agree - but there is a trade off b/t simplicity and customiziability (I just made up that word). Design is a compromise, and overall the Emag is pretty darn good. That said - i'd love to be able to tweak several parameters of the curve - just like you mention

nucleus said:
Frank, I want more spark advance on mine for smoother running lean of peak at higher manifold pressure. The Commander will only do it if I switch timing curves in flight which I don't like. One more thing to manage. I would like to leave the low MP advance where it is and be able to experiment with the advance at higher MP's, or the crossover point where they limit the advance. In other words I think that the pmag timing is too conservative for good LOP operation at lower altitudes. I'm open to ideas.

Hans
Click to expand...
 
YMMV

Just another data point, and perhaps not totally accurate, but I have flown with all three configurations; Two Slicks, a Slick and an E-Mag, and an E-Mag and a P-Mag. Going to one each, I saved one gph at cruise, and that is pretty close to accurate. Going to two electronic, I saved perhaps another .2 gph. Some, but not .5 as some say. As to power, I didn't seem to gain ANY with the switch to one each. MAYBE a little, but not significant. Going to two, I gained enough to add 5mph top at 8,000, WOT. My egt's dropped a bit and cht's didn't change enough to matter. My cht's have always been very good. The big difference in smoothness came when the second E- was added. I idle smoothly at 420rpm (on the ground, not down final.) Not like a CS for slowing down, but sure better than a 700 rpm idle.

Bob Kelly
 
Hmmmm...

nucleus said:
Frank, I want more spark advance on mine for smoother running lean of peak at higher manifold pressure. The Commander will only do it if I switch timing curves in flight which I don't like. One more thing to manage. I would like to leave the low MP advance where it is and be able to experiment with the advance at higher MP's, or the crossover point where they limit the advance. In other words I think that the pmag timing is too conservative for good LOP operation at lower altitudes. I'm open to ideas.

Hans
Click to expand...

That would be nice..I guess I'm a bit conservative when it comes to timing advance..When you talk of higher manifold pressures and LOP I guess I'm fearful of where the thing will actually detonate. Having suffered detonation once I know the stress on the engine is huge and temperatures go off the charts very quickly.

For me at least I don't do LOP ops unless I'm running a max of 24"MP..Not a real restriction..I mean i take off and can easily get to 8000ft or so where mp is below 24" before doing the big lean (I lean for ROP power in the climb)...Or if just putzing around I simply pull the throttle to get 24" and do the big lean.

With the Sam James cowl and standar A curve timing I get 160 to 161 kts at 12.5+ at 7.3GPH....Thats pretty darned good..Not sure how much more there is to be had by advancing the curve.

Thinking about it what we want is a brave soul to find out where detonation happens. Then we would know where the limits are..Volunteers?...:)

Oh I also run mogas (with ethanol sometimes) Which makes me a little cautious in this area too.

Frank
 
It's nice to read a thread about how the E/P-mags work rather than if they work. :rolleyes:

The E/P-mags does reduce the firing angle as MP increases, as stated earlier. How much depends on how far you push the power up, altitude, all the normal stuff. Still, you might end up with more advance than you would see with the fixed timing a standard mag offers.

The other thing that helps your performance/power is that the electronic ignition allows for larger plug gaps and a stronger spark, which improves performance regardless of the firing angle.

One thing the EICommander will do is display the current advance so if you climb up high, you can play with your RPM & MP to try and find the sweet spot for the ignition, thus improving your gph number. That is in addition to allowing you to tune the timing curve to your flight conditions, fuel, etc. Sounds like something the racers would like. (Mr. Axsom, racer Sir, are you listening?)
 
My Best Numbers So Far Dual PMags

My best numbers so far (since I actually calibrated my airspeed) were at 9500 MSL, full throttle, 2500 RPM, 171 knots true, 7.1 GPH, averaging 60 degrees LOP, B curve. That GPH is not completely calibrated yet, it reads a bit high. Much higher than that and my CHT's start climb (at least in warmer weather), and much below 8500 and the engine runs rougher and the EGT's climb, which tells me that I need more advance. I may buy a EI Commander yet, but I would like to modify the curve to what I want and just run one curve, not have to switch between them.

Hans
 
What?

nucleus said:
My best numbers so far (since I actually calibrated my airspeed) were at 9500 MSL, full throttle, 2500 RPM, 171 knots true, 7.1 GPH, averaging 60 degrees LOP, B curve. That GPH is not completely calibrated yet, it reads a bit high. Much higher than that and my CHT's start climb (at least in warmer weather), and much below 8500 and the engine runs rougher and the EGT's climb, which tells me that I need more advance. I may buy a EI Commander yet, but I would like to modify the curve to what I want and just run one curve, not have to switch between them.

Hans
Click to expand...

Your getting a full 10 knots more than me running LOP on less fuel...Quite honestly I'm AMAZED!

Frank
 
carguy614 said:
First, let me say, I love the Emag Pmag idea.
To all that have been involved, have these issues been resolved???
Hope so.
click on Emagair link from site below.

http://www.cozybuilders.org/

Regards,
Chris
Click to expand...
Chris,

Thanks for posting that link. That is old news and has been hashed over many times before. It turns out to be total BS. Another case where one guy with problem didn't like the answer he was given. Read about how many ignition problems he had with different ignitions before his engine destroyed the final P-mag. It sounds like he had a problem that wasn't related to the P-mags.

However, it serves to point out the need to make sure all those who are running E & P-mags should contact E-mag Ignitions and send them in for the latest upgrades, both software and hardware. (Nothing new for those who have done so recently. However, if you haven't sent your ignitions in for an upgrade because they are "working fine", it is imperative that you get them in. It will only cost you shipping. Compare that with the cost of servicing a traditional mag!)

Search this site for P-mags and read to your hearts content, thus the comment about it is nice to hear positive feedback.
 
frankh said:
Your getting a full 10 knots more than me running LOP on less fuel...Quite honestly I'm AMAZED!

Frank
Click to expand...

You saw that was true airspeed and not indicated, right? My plane is FAR from being aerodynamically optimized. My pitot-static-altimeter was calibrated/certified by Aerotronics and I calibrated the airspeed at a bunch of different airspeeds and altitudes on the GRT EFIS. It now matches well with the gps groundspeed. My fuel flow is more likely to be off, but since my last calibration change on the EIS it tends to need less fuel than what it tells me so that tells me that it is reading a little high.

You plane has the better fuel injection if I recall correctly. Probably a calibration thing. We should fly side by side sometime and see. I do think the Whirlwind could be worth a little speed. Which prop are you running? Other details on my bird that could possibly make a difference would be 9:1 compression ratio and a James cowl/plenum. Is yours 180 HP? Mine plane is a porker BTW, 1120 pounds, that definitely slows me down.

Hans
 
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YUp

nucleus said:
You saw that was true airspeed and not indicated, right? My plane is FAR from being aerodynamically optimized. My pitot-static-altimeter was calibrated/certified by Aerotronics and I calibrated the airspeed at a bunch of different airspeeds and altitudes on the GRT EFIS. It now matches well with the gps groundspeed. My fuel flow is more likely to be off, but since my last calibration change on the EIS it tends to need less fuel than what it tells me so that tells me that it is reading a little high.

You plane has the better fuel injection if I recall correctly. Probably a calibration thing. We should fly side by side sometime and see. I do think the Whirlwind could be worth a little speed. Which prop are you running? Other details on my bird that could possibly make a difference would be 9:1 compression ratio and a James cowl/plenum. Is yours 180 HP? Mine plane is a porker BTW, 1120 pounds, that definitely slows me down.

Hans
Click to expand...


The FI systems should be a wash..I do have a buddy with an almost identical airplane complete with SJ cowl and plenum like mine, with a Hartzell CS BA prop.

He is slightly..and I mean like maybe 1 kt faster than me at the same fuel flow..its so close it maybe just an instrumentation issue.

Now I have not truely calibrated my TAS, but it appears to agree with the GPS ground speed.

result is at 12.5 an above i get a TAS of 161 kts burining 7.3 GPH (that I have calibrated) of Mogas.

Maybe 100LL is 10 kts faster..and you a lot more advance..I run 8.5 :1 pistons, 180HP motor

Yours appears to be significantly faster..i have not tried running at a faster engine speed at cruise.

RV 7a right???..And RV8 would be faster.

I'd love to fly side by side and see what the difference is...Cus I want whatever you got..:)

Frank
 
We visited with the P-mag folk at OSH and were very impressed with the product. My friend with the 80% done RV6 will get a P-mag to go with the existing Slick. And I'll probably go with them if/when my Slicks head south.
I still can't get over setting the timing by gently blowing into a plastic tube after positioning the unit for best access on the accessory case. No buzz box required.
 
I still have the question: Is Brad or Tom a pilot, and are either of them flying behind their product on a regular basis?

Note, I have a qualified history to be asking such a question.
 
Re: "best numbers so far for dual P-mags by Hans Conser"

These numbers are identical to my observations with my 7A.

IO-360 M1, dual P-mags, 1130 empty weight. 170 kts true at 7.2 gph, 40F LOP

Martin Sutter
building and flying RV's since 1988
 
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