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Lycoming engine/Mag Question

Stockmanreef

Well Known Member
I emailed Van's about ordering the IO-390 engine from Lycoming. I asked the question about mags. Pmags, regular mags, etc.

Van's claim that Lycoming will only not sell dual electronic ignitions. So one could buy an engine with 1 P-Mag and one Mag. If you want two P-Mags then they will leave blanked off.

Any idea as to why?
 
My gut is that Van's is being conservative in terms of having at least one mag on the engines they provide - given the proven reliability, serviceability in the field, and independence from power source.

I ordered Thunderbolt option and talked with Jeff there who seems willing to offer some other options beyond the specs Van's has on their order sheets, but I don't have any idea how this applies to standard engines. I decided to go with one mag/one pmag for the reasons stated above - I'm conservative too.
 
Ken
I have one mag and one electronic. I have flown many different versions. As this appears to be your first build I would recommend two mags, ease of cervicability etc. It will one less thing to learn on a new plane.
Now after 4 or 500 hours when it is time for mag servicing, that would be a good time to consider a new or combination of ignitions. With good data from your first 500 hours you will really know if it was worth the money.
Remember you built the plane and you can modify it.

Most of my cross country flights are 10000 feet or more and the electronic ignition works well there. After 500 hours or so you will also know how high you typically fly.
 
I ordered my IO-360-M1B with a pMag and the other side blanked off. They did include the mag gear I?ll need for the second pMag. I have dual pMags on the RV-8A for 700 flawless hours and will soon replace the mags on the RV-10 with their new six cylinder pMags.

I offer that the reason why Van?s will not sell the engine with dual pMags can be traced to lawyers (my opinion, no facts).

Carl
 
Thanks for the responses. Based on the email I got back from Van's, it sound like this was a Lycoming decision and not a Van's decision.

Yes, first build so I don't know much about mags other than the obvious.

So what is there to learn with a P-Mag? I know they are electronic and generate their own power, like a regular mag. And one is supposed to get better fuel efficiency. a gallon or so per hour less, if you do lots of cross country flying.
 
You might check with Thunderbolt. They seem to be more agreeable about leaving bits off you don't need for EI/EFI.
 
I Just went through this

Lycoming told me at Oshkosh last year that due to legal reasons they were unable to fit dual pmags. So nothing to do with Van?s.

There is a few things that need to be considered when fitting dual pmags with a new engine.

1. You need to tell Lycoming as they will install short studs on the blanked magneto.
2. They give you $500 off for not fitting the magneto.
3. You will need to purchase a magneto ring gear for the pmag.
4. You need the magneto installation kit, which is the two small brackets available from ACS.
5. You will need a tach drive cap, as RPM is taken from the pmags.

Rgs Chad
 
2 Pmags

Ken, I just got my IO360 engine from Vans. Got the Prop discount, Long
Term Pickling, and Free shipping. Vans took off one mag and installed Pmag with their deal. I had talked with Lycoming, they took off the 2nd mag, gave me $500 credit, then installed 2nd Pmag charging me $1200.
So when the engine arrived I had two Pmags for $700 more. If you need I can find the guy's name and number at Lycoming.

Allen,
Very Slow Build 7A
 
I got mine from Vans and chose one standard mag and one emag.

Downside of emag:
- Need a map sensor line
- New way of setting the timing
- Not self sustainable if RPM below around 900

Upside of emag:
- Engine runs better
- Engine starts better
- You get a free tach sensor

what the heck is a map sensor line?
Also, not sure how new way of setting timing is a downside, setting timing on PMAG is lots easier than Slick.

To the original question, I first ordered my engine with one PMAG and blank on the other side so I can add a second one since Lycoming wouldn't ship with two EI. I end up changing it with no MAG at all and going to install two PMAG myself, small saving this way but installing PMAG is very easy.

Hope this helps.
 
but the benefit from having two instead of one seems small so I just went with the easiest option. :eek:

You are correct on this. In my RV7, I first went with one PMAG and then the second. The difference on the first PMAG was very noticeable but with the second I could hardly tell the difference.
 
I got mine from Vans and chose one standard mag and one emag.

Downside of emag:
- Need a map sensor line
- New way of setting the timing
- Not self sustainable if RPM below around 900

Upside of emag:
- Engine runs better
- Engine starts better
- You get a free tach sensor

The RPM cut off, in the event of an electrical failure is close to 800 RPM and isn't an issue as your RPM will be higher than that I flight and will only drop below that number when rolling out in the runway and that is a great place for that to happen.
 
With one Slick and one PMag in a hybrid system, may I ask how you guys connected the tach? I want to have a speed signal from both ignitions for the RPM drop test.

My existing tach input signal range is 100-1000 vac which is well above the 12v output from PMag terminal 6. Did you have to buy a new tach, modify your existing tach, or install a signal conditioner?
 
With one Slick and one PMag in a hybrid system, may I ask how you guys connected the tach? I want to have a speed signal from both ignitions for the RPM drop test.

My existing tach input signal range is 100-1000 vac which is well above the 12v output from PMag terminal 6. Did you have to buy a new tach, modify your existing tach, or install a signal conditioner?

Connect your EFIS tach signal to pin 6 on the P-mag.

When the P-mag's P lead is grounded and the plugs are not firing the electronics are still alive and continue to put out a tach signal.
 
I have dual pMags on the RV-8A for 700 flawless hours and will soon replace the mags on the RV-10 with their new six cylinder pMags.

Carl

:D:D:D:D:D:D:D:D:D:D

Good luck with that. A year before I flew, I was told that it would be ready for me to fit in time - I've now been flying 3 years and the Pmag-6 is still coming "soon".....
 
Ignition Choices from Titan engines

I read a lot of discussion about Thunderbolt but little about Continental Motors' Titan. Titan has had years of successful experience with dual electronic ignition systems on our engines. Titan will configure the way you want and has Continental Motors ( Bendix ) magnetos which have much better quality than the alternative brand. Consider Titan, you get a lot more innovative features and benefits for the buck.
 
Connect your EFIS tach signal to pin 6 on the P-mag.

When the P-mag's p-lead is grounded and the plugs are not firing the electronics are still alive and continue to put out a tach signal.

Hi Bill,

Let me clarify. I do not have an EFIS. It would be a non-issue with an EFIS. I have steam gauges and a stand alone Horizon P-1000 digital tach (http://horizoninstruments.com/) with speed input signal range 100-1000 vac....for direct connection from magneto p-leads.

It boils down to whether or not the voltage/freq characteristics of the PMag p-leads are functionally compatible with the existing tach input voltage/freq signature from magneto p-leads. This would allow PMag installation using existing p-lead wiring to the ignition switch and tach.

Seems this wheel must have been invented already by those with standalone digital tachs.

Cheers!

Tom
 
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