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E-mags

Chippster1

Active Member
Has anyone out there installed an E-mag? What do you think?
I have a Lightspeed ignition and a standard Mag. Will I notice any difference if I go all electronic?
 
There have been plenty of RV people that have installed Pmags (me included). The difference in performance with one electronic ignition and one standard mag is noticeable. The increased performance difference with a second electronic ignition is much less noticeable. That?s because your Lightspeed, or any electronic ignition system in a EI/Mag system is doing most of the work. Your mag is there to provide an ignition source backup - self powered - in case you EI system malfunctions. And it does this at a reduced efficiency level, but it gets you safely on the ground. The down side is the usually necessary periodic maintenance with the mag that can be expensive (500 hour), the expensive spark plugs, and the reduced efficiency due to primarily fixed ignition timing. Will a second EI pay for itself? I don?t think so. That?s my opinion, but I think it would take a few 500 hour Mag tear down inspections coupled with an EI system that has been completely trouble free (unlikely) before the marginal improvement with a second EI would justify the expense. The first EI is pretty easy to justify - 1 gal per hour on an O-360 approximately is somewhat normal. The second one won?t give you that much more.
 
I?m running two P-mags. I really like them. As previously mentioned, changing the first mag to a P-mag provides of the most benefit. I want my backup to be just a great as the primary. So I have two. I love seeing mag drops in the 30-60 rpm range.

Bevan
 
I?m running two P-mags. I love seeing mag drops in the 30-60 rpm range.

That?s exactly what I get with my two slicks! That said, mine are coming up on their 500-hour mandatory inspection so I will probably switch at least one of them to a pmag for the fuel savings if nothing else.
 
We have two P-Mags on our IO-360 and have been delighted. NGK auto plugs, swap them on the annual.

Hot and cold starts first time.

Can't be definitive about fuel savings, power etc as we never flew with dumb mags.

BTW, the 500 hour inspection is a service bulletin and therefore isn't mandatory, it is a recommendation by the manufacturer to protect themselves ;)
 
BTW, the 500 hour inspection is a service bulletin and therefore isn't mandatory, it is a recommendation by the manufacturer to protect themselves ;)

Ummm... Taking the legal discussion off the table, whether it is a Service Bulletin, Airworthiness Directive or whatever, it's absolutely necessary. There have been many tales of magneto woe documented on this discussion forum. There are so darned many things inside Slicks that can and do go wrong.

Just an aside here, but I'll tell my little story of my brand new, zero time 4371 mag. It was shipped attached to my brand new Lycoming engine. Several years later, when I was prepping for first engine start, I opted to send it out to a magneto shop for an IRAN visit. I could hardly believe my eyes when I saw the work order - the list of SBs that had been incorporated during that shop visit was as long as your arm. One of them would have almost certainly led to premature failure since our mag was one of those shipped with soft brushes.

With all that having been said, ignoring the factory-recommended 500 hour magneto inspection is something one would do at their own peril.

The right ignition on our O-360 started with a 4370 mag that was replaced with a P-Mag prior to the first engine run. Based on Lycoming performance charts we are saving on the order of 1 gallon per hour of fuel with the P-Mag installed. Installing electronic ignition is a no-brainer with respect to financial pay-back.
 
What is the periodic inspection regimen for E-mags? What does the manufacturer recommend?
 
What is the periodic inspection regimen for E-mags? What does the manufacturer recommend?

100 hours.

You just pull them off and check to make sure the cotter pin is intact and the gears aren't loose.

Reinstall and re-time.

Should take about 30 minutes if you have easy access to the bolts.

Edit: Timing is really easy on these, you just set your prop and blow in the manifold pressure hose.
 
I don?t argue with the point made that one pMag produces most (but not all) of the gain when compared with dual pMags. I remind people however that the pain of running mags should not be ignored. The hours wasted on cleaning grossly overpriced aviation plugs piles on top of knowing you have a big nylon gear waiting to eat itself, SBs and such.

I was thrilled when I found out I can order an engine from Lycoming with one pMag and no mag at all, but get credit for the missing mag. The second pMag arrived from Brad before I even got the engine shipped from Lycoming.

Carl
 
Titan Engine Ignition options

Titan engines are available with Continental Motors (Bendix) magnetos that are much less troublesome than Slicks. Titan also can supply P-mags, Lightspeed or EFii System 32 with a new engine.
 
Idle & Hot Start Difference

Did any of you notice a change in idle (smoother) or hot starts when switching to an Emag/EI?
 
Many carb'd Lycomings don't like to idle very slowly. With the P-Mag I can idle at 600RPM if I want to. I don't generally idle that slowly, save for a brief check during run-up to ensure the engine will continue to run at idle.

Starts are a no-brainer.
 
Has anyone out there installed an E-mag? What do you think?
I have a Lightspeed ignition and a standard Mag. Will I notice any difference if I go all electronic?

Ted, I’ve got exactly your setup. I’ve got an IO360 with a Plasma III on the right side and I just finished replacing my Slick impulse mag with a Pmag on the left side.
So far, cold starts require very little priming with the boost pump; about 1 second, compared to 3-4 seconds with the Slick. Starts in less than one revolution. Hot starts are a non event.
CHT’s are now running about 20 degrees hotter at 23 squared, 350 degrees.
Fuel burn has gone from 8.7 GPH to 8.1 GPH.
Auto plugs, cheaper and better.
Timing is a non event. Like has been mentioned, it only takes a few minutes.

Did any of you notice a change in idle (smoother) or hot starts when switching to an Emag/EI?

Idle is smoother and I can have it running smoothly at 500 RPM. Not that I keep it there, just sayin’.

My only regret is that I didn’t switch sooner.
 
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Hi Karl, Are the changes you mentioned after replacing the Slick with the PMag? Did you already have the Plasma III? Curious, as I have a Plasma III on one side and am considering replacing my Slick on the other side with an E-Mag...
Thanks!
Greg
 
Hi Karl, Are the changes you mentioned after replacing the Slick with the PMag? Did you already have the Plasma III? Curious, as I have a Plasma III on one side and am considering replacing my Slick on the other side with an E-Mag...
Thanks!
Greg

Hi Greg. Yup, I?ve had the Plasma III on the motor since day one. The changes I mentioned were after I replaced my Slick 4371 with a Pmag. The reduction in fuel burn was noticeable when running at 23? MAP and 2300 RPM, what I would call ECON cruise at 170 KTS. I did change the timing by about 2 degrees and the CHT?s are now about the same as what I had pre Pmag. Hot starts on my fuel injected motor are a non event. The prospect of getting the latest Slick service bulletin done, the fact that I was approaching the 500 hour inspection, the Rube Goldberg way of having to time a mag, and the weight savings of a Pmag drove me to replace it. Only have about 30 hours on my new setup but so far so good, and I would not go back. Your mileage may vary ;)
 
Worst ignitions I've ever used. I ran a pair with the EI Commander. They shifted timing during flights and over heated the cylinders. There are many horror stories with e-mags / p-mags. But some people swear by them. Each to their own.
 
Left or Right?

I?m running dual Slick 4371?s on my O-320, but planning to eventually change one to a Pmag. I?ve been curious, does it matter which side the Pmag goes, left or right?
 
I’m running dual Slick 4371’s on my O-320, but planning to eventually change one to a Pmag. I’ve been curious, does it matter which side the Pmag goes, left or right?

Most people install on the right side. You need the impulse that's on the left mag (usually). If you want to start on both.
 
I?m running dual Slick 4371?s on my O-320, but planning to eventually change one to a Pmag. I?ve been curious, does it matter which side the Pmag goes, left or right?

Assuming you have an impulse mag on the left side, put the pMag on the right.

Reason - typical startup is with the impulse mag only, the other is off until the engine starts. Replacing the right mag with the pMag lets you start on both the mag and the pMag. If you are still using a clunky key ignition switch this will not be possible without modification.

I also recommend rerunning the remaining mag plug leads to all top four plugs. That way the bottom plugs are all on the pMag - this will mitigate bottom plug fouling issues.

Run like this until you need to replace the remaining mag - then add the second pMag. On my planes I just start off with two pMags.

Don?t be surprised if the pMag RPM drop is more than the mag when doing the mag check. Depending on RPM and how you timed the mag and pMag, the mag may be at a more advance timing then the pMag at your 1700 or so RPM mag check (thus when you turn off the mag you get a higher RPM drop). At flying RPM the pMag will be at the same timing or more advanced than the mag.

Carl
 
I like the idea of replacing the right non-impulse mag with your first Pmag. If you have a key start switch you will have to remove a jumper on the back of it so it won't ground out the Pmag on start. Then both ignitions help start the engine.

Jim
 
I have dual impulse mags, so it sounds like it doesn?t matter which one is removed and replaced with a Pmag. I have removed the key switch jumper, so I?m starting on both mags. Would I leave that jumper out?
 
I have dual impulse mags, so it sounds like it doesn?t matter which one is removed and replaced with a Pmag. I have removed the key switch jumper, so I?m starting on both mags. Would I leave that jumper out?

Yes.......
 
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