IO-540 Ignition Options

[J Twilbeck]

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,

[Mike S]

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.

[J Twilbeck]

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]

Thanks Mike!
That's a great list to research. Thank you.

[Mike S]

Originally Posted by J Twilbeck

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!

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

Breath holding not recommended.

[rocketbob]

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.

[rcpaisley]

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 robert@protekperformance.com.

Good luck with the project!
Robert Paisley

[vlittle]

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.

[rcpaisley]

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

[logansc]

Robert: Does EFII have a six-cylinder system?