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IO-540 Ignition Options

J Twilbeck

J Twilbeck

Well Known Member
All,
Does anyone have a good reference (website, etc) explaining the ignition system options for the IO-540? Or can explain directly from the knowledge base we know as VAF :).
-Magneto vs electronic ignition
-E-Mag vs P-Mag (if they are even making these for 6 cylinders yet)
vs lightspeed, etc
-Pros and Cons of each

In short, I'm looking into Electronic Ignition options for the six cylinder 540 and I would like to know what others before me have done.
Thanks,
 
Mags.

Mags with G3 ignition modification.

Lasar mags.

Lightspeed. One or two-------your choice.

EFII has a 6 cyl unit in production IIRC.

As far as I know, Pmag is still vapor......would be nice it they actually go into production.

Barrett had an electronic ignition in the works, dont know the current status, you need to check with them.

Jeff Rose-----dont know if they do a 6 cyl or not.

Simple Digital Systems, I think they offer a 6 cyl. Seem to remember that this is the ignition side of EFII??

All I can think of at the moment.
 
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Update

Just spoke with E-Mag (they don't make emags anymore only pmags) and they plan on debuting the six cylinder pmag at Sun N Fun this year (2013). So we'll see!
 
J Twilbeck said:
Just spoke with E-Mag (they don't make emags anymore only pmags) and they plan on debuting the six cylinder pmag at Sun N Fun this year (2013). So we'll see!
Click to expand...

Saw the unit at Osh in 2011. Was told it would be available by the end of the year.

Breath holding not recommended.
 
I wouldn't get too optimistic about a 540 pmag. Others have tried driving a geared pickup sensor and have failed on the 540. There is a lot of ringing in the accessory drivetrain which is fine to drive a magneto but not so good for an electronic ignition. The 540 has a 1.5:1 drive ratio on the mags, which is different than the 1:1 ratio of the 4-cyl engines.
 
EFII 540 ignition

Hi Justin,
We have a nice dual ignition for the 540. It uses a very robust billet crank trigger assembly and has load compensation. Load compensation is a few degrees ignition retard at the highest manifold pressures. This gets you to normal mag timing at high power and provides several degrees more advance in cruise for better economy.

Our system is fully programmable and can be adjusted for compression, or type of fuel with an optional programmer. It is also a modular system that can be upgraded in the future to full electronic engine management with electronic fuel injection.

If you have more questions, send me a note at [email protected].

Good luck with the project!
Robert Paisley
 
There are two main technologies used for electronic ignitions.

1. Capacitor Discharge (CD) which uses the coils as a transformer to produce very high voltage, but short duration sparks. Current systems fire the plug multiple times during an ignition event to make sure even very lean mixtures burn.

2. Inductive systems similar to conventional coil-breaker ignitions but use electronic switches and higher currents to generate a long-duration moderate voltage spark that will ignite very lean mixtures.

Both types of systems work fine.

I chose the Electroair (Jeff Rose) system for my IO-540 because I am a fan of the inductive systems. It's inherently simpler and the spark plug voltages are lower so there are fewer issues with spark plug wires or the plugs themselves and there are fewer electromagnetic interference issues.

Whatever system you use, it's more important to research the company providing the technology rather than the technology. For example, the Electroair is (was) based on a volume production system used for auto racing, modified for aircraft use. In fact, I used the automotive datasheet to install my system!

Electronic ignitions are best for high-altitude lean-of-peak cruising where they can fire very lean mixtures and thus provide better fuel economy. Down low, it's probably not worth the cost and complexity.
 
ignition info

Hi Vern,
That was good info.
A little more on the down low performance:
Spark energy is part of the equation. The timing curve provided by an electronic ignition is very important as well. Mag timing is fixed and set for the absolute worse case of operating conditions to prevent detonation. This is a huge compromise which reduces maximum power and decreases maximum efficiency.

A proper timing curve coupled with a hot spark can give you as much as a 10% power increase (sometimes more). A load compensated timing curve (using a MAP sensor) can let the cruise timing float to a greater advance for improved efficiency in cruise. Our customers commonly report a gallon per hour in cruise savings with a 360 engine.

There are other benefits of going electronic such as MUCH better starting and a smoother idle. Not to mention, your ignition doesn't wear out every 500 hours like a mag. Actually, the mag starts wearing out from day one. It just takes 500 hours before the process is completed.

You will find pretty much all cars these days have high energy inductive ignitions. These give you the highest spark energy, longest spark duration and most reliability. The Electroair system as well as our system (EFII) fall into this category.

Robert Paisley
 
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More horsepower, really? Now that would be a first for electronic ignitions. Except for high performance, carefully tuned race engines I can't see any scenario where peak horsepower of a Lycoming operating at full throttle, max rpm would be measurably enhanced by an electronic ignition.

Better efficiency, I believe.
 
Robert: Thanks for the info. I just don't see anything on a six-cylinder system on your web site. Can you direct me to the information? I'm especially interested in your official views on a single system paired with a Slick.

Thanks...


Lee...
 
EFII for 540

Hi Lee,
We don't have all our part numbers on the website.
(They will be soon:)

I will PM you with more info.
Robert
 
EI for the 540

Justin:
I've had LSE systems on a hopped up IO-320 and currently on a LYC O-540 in an RV-8. If you install the LSE by the directions, they will never miss a beat. I recommend the crank position sensor magnets n the flywheel. You can use auto plugs (WAY cheaper than aviation plugs) that you can toss out each annual and replace. When I turn the mag off on the run up check the RPM doesn't hardly drop 20-30 RPM! The MAG is an afterthought.

Larry
 
Ignition System Info

Thank you everyone for your input. I have pulled a lot of this research together into a single post on my blog if anyone is interested. I'm not trying to direct people to my website but the quantity of info I have is too much for this forum. Please note that the info I have pulled is for informative purposes only. For the new builder that wants to know his/her options when deciding on an ignition system. There is no release of an amazing new study or new information (most comes from the vendor's website) it's only a centralized information point to assist anyone following behind me in making their own informed decision.

In summary I discuss
-Links to vendors websites
-What Van's Engines ship with.
-Classic ignition system (ie mags).
-Why use an electronic ignition?
-Cons of electronic ignition.
-Dual electronic ignition vs a split system
-Electronic Ignition Options Including
- P-Mag
- Lasar
- G3 Ignition
- Light Speed
- ElectroAir
- EFII

Enjoy
http://buildingrv10.blogspot.com/2013/03/rv-10-io-540-ignition-system-decision.html
 
Pro's and Con's

I have not seen anyone discuss the issue of the spark being VERY accurately delivered on each combustion cycle.

This is something that has been found to be very accurate and something less desirable than an ever slightly variable result.

I had not considered this before now, until two very smart engine guys (from opposite sides of the planet) explained this to me recently. It is amazing what data some folk collect during tests that are for certification purposes.

It may not matter to you, but it was noteworthy. One thing a Magneto does far better.
 
RV10inOz said:
I have not seen anyone discuss the issue of the spark being VERY accurately delivered on each combustion cycle.

This is something that has been found to be very accurate and something less desirable than an ever slightly variable result.

I had not considered this before now, until two very smart engine guys (from opposite sides of the planet) explained this to me recently. It is amazing what data some folk collect during tests that are for certification purposes.

It may not matter to you, but it was noteworthy. One thing a Magneto does far better.
Click to expand...

I am not understanding what you are saying here. Are you saying a magneto with a gear drive and points has more accurate spark timing than a crank triggered electronic ignition?

In any case, Lycoming's own dyno testing shows minimal changes in power with fairly large variations in ignition timing.
 
Areed Ross, the power stays pretty much the same and in the case of advance, it reduces power after a few extra degrees due to the work required to compress an expanding gas.

As for the magneto, no that is the opposite of what I was saying. The magneto is far less accurate, and that may be a good thing. The actual spark firing is nothing like what is set up in a static timing test, the actual spar event happens much later.
 
RV10inOz said:
Areed Ross, the power stays pretty much the same and in the case of advance, it reduces power after a few extra degrees due to the work required to compress an expanding gas.

As for the magneto, no that is the opposite of what I was saying. The magneto is far less accurate, and that may be a good thing. The actual spark firing is nothing like what is set up in a static timing test, the actual spar event happens much later.
Click to expand...

The spark occurs exactly when the spark occurs. You could say the ignition event also happens pretty much simultaneously. The combustion process takes a lot more time relatively speaking. In the end, we want PCP to occur 18-22 degrees ATDC. We do want accuracy of spark event to ensure PCP happens at a predictable place in the crank rotation cycle. Pressure plots also show that no 2 firing cycles are the same.
 
Ross, you are getting warm now. I know you are onto it.

The variation with a magneto is greater (less accurate) combined with the cycle to cycle variability this may have a longevity benefit.

Watching pressure traces in real time and being able to switch from one to the other instantly is truly enlightening. The EI systems bring things far closer aligned most of the time.
 
J Twilbeck said:
Just spoke with E-Mag (they don't make emags anymore only pmags) and they plan on debuting the six cylinder pmag at Sun N Fun this year (2013). So we'll see!
Click to expand...

So, anyone any news? Or are we still turning blue holding our breath........?
 
Mike S said:
Mags.

Mags with G3 ignition modification.

Lasar mags.

Lightspeed. One or two-------your choice.

EFII has a 6 cyl unit in production IIRC.

As far as I know, Pmag is still vapor......would be nice it they actually go into production.

Barrett had an electronic ignition in the works, dont know the current status, you need to check with them.

Jeff Rose-----dont know if they do a 6 cyl or not.

Simple Digital Systems, I think they offer a 6 cyl. Seem to remember that this is the ignition side of EFII??

All I can think of at the moment.
Click to expand...

I talked with Rhonda at Barrett Precision Engines on Monday and she said that since her father had to retire with health problems last year there hasn't been much work done on their electronic ignition project. It'll happen eventually.....or maybe not. I'm getting an engine from them late this month for my -10 but they have no option for ignition of their own.
 
I asked my friend to look at all the options for E-ignitions while he was at Sun-n-Fun. As I understand it, Emag said they would have their product out at Oshkosh this year. :confused:
 
JDanno said:
I asked my friend to look at all the options for E-ignitions while he was at Sun-n-Fun. As I understand it, Emag said they would have their product out at Oshkosh this year. :confused:
Click to expand...

Yeah, right...........

I am rapidly losing faith with Emag and starting to look at other options. As Mike Starkey said "breath holding not recommended".
 
Here is a recent email exchange I have had with EmagAir:

Hi Brad, me again......

There were rumours that the P200 would be released at S&F but it has been and gone with no announcement.

I understand the "commercial in confidence" aspect but I think you owe it to all of us who have been waiting patiently for best part of 2 years to let us know exactly what the problem is with the P200. Is it simply a matter of certification paperwork (if that is the way you are going) or is there some almost insurmountable problem? I have heard that the 6 cylinder requires a 1.5:1 gearing which is problematic - is that where the issue is?

Please give us some information we can work with other than "we expect it in 2-3 months". If you are not going to produce this thing then I will think again and move on

Regards

Paul



Hi Paul:

I was planning on taking a working 6 cylinder (Series 200) to Sun N Fun. So ?I? was the one who started the rumor. I took a display version of the six to the show as Tom needed the working models at the shop to continue testing. You are quite right, it?s taken quite a while to get to this point and customers have been more than patient. If people need to move on without us, it will be our loss and I fully understand. We are quite committed to the series 200 and equally committed to getting it right. It remains a very high priority for us.

The engineer has not released it for production as yet.

Kindest Regards,

Brad Dement


Nice and polite but all very unsatisfactory. It's moved from giving estimates to "we are committed" and "high priority". I can't help feeling there is some fundamental, insurmountable problem and the whole thing is going to end up getting canned...........
 
EFII six cylinder

Hi Andy,
I don't have specific performance data. However we seem to have a continual stream of customers that tell us that their engines run better and their cruise efficiency is improved. We can also tailor ignition curves for individual customer requirements. You also have the option to upgrade to include electronic fuel injection in the future if you choose. Installation is pretty basic.

Robert
 
Robert, reading the details on your electronic fuel injection, it really eliminates the mixture control in the cockpit? How do you go about leaning the engine for LOP or is that controlled via the electronic system? Is it compatible with GRT and other displays or do you have to mount you electronic display in the panel?
 
EFII questions

Hi Tim,
Yes, the mixture control cable goes away. Our system incorporates a "mixture adjust" potentiometer to aid in fuel map tuning. During normal flight ops, the mixture adjust knob does not need to be used.

The fuel map can be tuned to automatically lean the engine when you are at cruise power levels if that is what you desire. Alternatively, you can leave the fuel map a little on the rich side during cruise (or any other part of the power envelope) if that is how you fly. If you like to fiddle with things when you are in cruise, you can leave the map on the rich side and temporarily lean using the mixture adjust knob for lean of peak ops.

The bottom line is that the system can be setup to operate however you prefer to fly.

The GRT and MGL equipment is directly compatible with our Fuel Flow output.
Other monitors may require a dual flow sensor setup to monitor fuel flow. Fuel flow is also directly displayed on our programmer.
Our tach signal is a 12v square wave signal that is compatible with all monitors.

The rest of your engine monitoring functions and sensors are independent of our system and behave as they would with any other fuel system.

Robert
 
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