What Ignition to buy? My choice narrows

[straight-n-level]

First of all, I would like to thank you for all the input on this topic.
After researching and reading most all of the posts, and a few phone calls. I have narrow my decision down to 2 possibilities, E-mag, or the G3i system. My one requirement that I would like to have is to have at least 1 magneto for a redundancy back up. I like the ease of installation of both systems. A lot of the E-mag users seem to be getting good results with one mag and one EI. As I understand, 2 EI systems would run smoother than just ? a system though. But, there seems to be some opinionated pros and cons out there on this type of ? configuration, and I?m still curious. If there are 2 separate EI systems advancing and retarding independently, how can they be in sync, and if a single EI system with timing advance has any effect on the later timed mag or components. Is there some experience with this? The other system that intrigued me was the Generation 3 ignition systems. The system make good sense to me, the magneto modification looks simple, and straightforward on the website. I found some brief G3i write-ups by Larry Vetterman, and various other forum posts and they seem to be all good. Is there more end user information on G3i systems out there? All the information and experience on this forum that has been provided is great.

Sincerely,

T. Mitchell

[breister]

Suggest you read through the posts in the Electronic Ignition area of the forums. Lots of opinions.

While I do not pooh-pooh the units you are considering, I would be curious why you would not be at least considering the LightSpeed. From reading failure reports over the years it appears that the biggest causes of failure of any of the EI systems are heat and vibration - both principally occurring when the electronics package is located forward of the firewall. Too, some of the EI units apparently have a failure mode which can cause excessive timing advance which can damage the engine - but I have never heard of that occurring with the LightSpeed units even thoug I have asked that question here on this forum, which probably represents the largest group of experimental flyers in the world.

As for your thought on 2 being better than one: A substantial number of people, myself included, run a single EI. The mag spark, which generally fires after the EI, is simply "wasted" but the EI spark is so hot that it does fine all by itself. On the ground run up mag check most people see that there is virtually no rpm drop when running on just the EI. On the Cafe numbers, if there is a 10 percent maximum efficiency gain using two EIs, 7-8 percent of that is recognized with a single EI so you don't lose much in performance.

Anyway, all that being said most people seem to be happy with at least one EI. If you choose to use two EIs, it is recommended that you have a small battery driving them that is electrically protected from the main bus via a diode (e.g. the main bus can charge that battery, but if the alternator fails the EI battery will only power the EIs, not the main bus). That gives you an extra layer of protection from total electrical failure, so that even if you have to turn the battery master off your EIs are still powered.

[nucleus]

Why not P-mags?

[Steve Sampson]

Originally Posted by breister

On the ground run up mag check most people see that there is virtually no rpm drop when running on just the EI.

I run two P-mags and am pleased with them, but certainly feel you should use whatever you feel comfortable sitting behind.

I was mulling over what Breister said though. With two P-mags I see a significant drop when I turn either one off. Perhaps 80rpm. So, if it is typical not to see a drop when you turn the conventional mag off, but you would see a gain if you could instantaneously replace it with a second electronic mag., it would seem that one of each is not optimally efficient.

As I said before though, peace of mind is key.

[Finley Atherton]

Not sure if this has been mentioned or is relevant to you, but if you plan to have a carburetor then the anecdotal evidence that I have read is that you will have a better chance of running LOP with dual EI. I have a carb 0-320 with one mag and one LS Plasma III and can just run all 4 cylinders LOP (WOT and carb heat). If I was starting again I would seriously think about dual EI to better run LOP. Then again, if I was starting over, I would get an injected engine with balanced injectors.

Fin
9A

[N941WR]

Originally Posted by straight-n-level

A lot of the E-mag users seem to be getting good results with one mag and one EI. As I understand, 2 EI systems would run smoother than just ? a system though. But, there seems to be some opinionated pros and cons out there on this type of ? configuration, and I?m still curious. If there are 2 separate EI systems advancing and retarding independently, how can they be in sync, and if a single EI system with timing advance has any effect on the later timed mag or components. Is there some experience with this?

The issue really isn't that bad, just like when your run one mag and one EI, the ignition that fires first burns most, if not all the fuel. Also, if you run EI, you need to have a larger gap for the high intensity spark. This is one reason so many of us run auto plugs. The larger spark helps ignite the fuel mixture and helps with the burn. Thus the lagging ignition really doesn't do a great deal. That's why you get about 75% of the benefit with one EI and the 2nd doesn't add a great deal.

All of the ignitions you have mentioned are good, no question about it.

If you elect to run duel EI's, then P-mags are the way to go, IMHO. Although a number of people run duel EI's that are not self powering, this requires a backup electrical system, just in case. One of the things that bothers me with many of the the EI's out there is the number of connectors and wires required. The P-mags are easy to install, time, and wire AND they just work. With P-mags, you can install two and have the same reliability and independence as with magnetos. The other EI's, as I said, typically run with a standard mag in the other hole.

In your research I'm sure you found a number of issues regarding issues with the E & P-mags, the good news is those problems seem to be behind them and the company has been very forthright in dealing with issues.

The decisiona comes down to, which ignition do you feel comfortable flying behind, and that is all that really matters.

[BikePilot]

There is quite a lot of data here http://cafefoundation.org/v2/research_reports.php on the results of running various combonations of EI and mags.

[7DeltaLima]

T. Mitchell,
I've put the G3I on my -10. It's easy to install but it'll be a few more months before I have any performance numbers. liked the idea of using the mags. If the g3i goes belly up, turn it off and it's back running on the mags.

Doug.... building of -10 slowed by required flying of the 7A

[SvingenB]

Originally Posted by BikePilot

There is quite a lot of data here http://cafefoundation.org/v2/research_reports.php on the results of running various combonations of EI and mags.

This was very interesting. Effective fuel distribution and intake is more important than EI. They also concluded that it is only above 10000' that EI will have any real benefit, but the improvement above 10000' is large.

BTW, Anyone know why they mountet an Ellison TB on a IO-360?

[Geico266]

Originally Posted by breister

While I do not pooh-pooh the units you are considering, I would be curious why you would not be at least considering the LightSpeed. From reading failure reports over the years it appears that the biggest causes of failure of any of the EI systems are heat and vibration - both principally occurring when the electronics package is located forward of the firewall. Too, some of the EI units apparently have a failure mode which can cause excessive timing advance which can damage the engine - but I have never heard of that occurring with the LightSpeed units even thoug I have asked that question here on this forum, which probably represents the largest group of experimental flyers in the world.

You must have missed my post about Light Speed Ignition going belly up in flight causing advanced ignition, rough running engine, high temps, and an emergency (on field) landing. I removed the EI and replaced it with a mag.

Below is a link to the wire used in Light Speed ignitions. It is building speaker wire.

http://geicodevelopment.com/light_speed_engineering