Does anyone have any experience with G3I's MSD electronic ignition system they can share?

http://www.g3ignition.com/index.html

It works with conventional mags. The claimed benefits are a smoother running engine, use of automotive style plugs, increased fuel economy, and a slight increase in power. The downsides appear to be cost ($1,300 range), additional weight of about 4 lbs, and added complexity.

Ever since I began building in 2005, I've researched the various systems every few years to see what might be promising. For a long time, probably 7-years, I've had high hopes for the E/P-mags but for 6 cylinder engines they have been very slow to get them into the market place and it appears they are still delayed and not yet available. They have made promises and taken deposits but have not delivered. It may still be a while yet before that happens.

I looked at the the G3i system a few years back and thought it had potential and still do so I'm curious to hear from those who have first hand experience with this system or is at least close to others who have. I'm loath to add additional weight so that is my personal biggest draw back to getting one.

I'll likely be replacing the PC680 battery (~15 lbs) with an EarthX (~5lbs) so if I were going to add a G3i, that would be a good time to do it and I'd still have a net weight loss. The other consideration is I really doubt that I'd notice much performance gain as nearly all of my flying is below 10,000 feet. I've read the stuff on the Van's site, but most of that is 2011 or older. They make reference to even older CAFE reports suggesting that there isn't much benefit to EI below about 10k. So unless I can find enough information to convince my self of the benefits, I'll forgo the expense and weight. However, I wanted to ask the collective brain trust on this site what their experience is with the G3i or other EI systems installed in utility/bush style aircraft.

Have you checked out the EFII system? flyefii.com The beauty with this system is that you get both electronic fuel injection and electronic ignition all in one box. For those that don't want to utilize the electronic fuel injection aspect of the system can use it for just its electronic ignition...and vice-versa. I built and am flying an RV-7 and have the EFII system on my airplane and I really like it a lot and it truly brings these old designed engines into modern times....as far as ignition and fuel injection is concerned. My next build is going to be a Carbon Cub and I'm planing on installing the EFII system on it as well.

No experience with G3i.

After considerable research and interviewing some users and the mfr, I'm planning on using FlyEFII in my Bearhawk. I think you're onto a good idea with the electronic ignition, Blackrock. The Vans Airforce site seems to be the richest in terms of anecdotal information on these systems, you might consider posting and asking there too since your search didn't turn up anything recent.

Lightspeed seems to have a lot of users, and Electroair has made a lot of progress in getting their systems certified. I agree the P-Mag concept is the coolest but there's no reason to believe they'll have a 6-cylinder version available any time soon.

As for benefits of EI, one of the biggest for me is the timing retard for startup which makes for easier starts which could be valuable to EFI users. Configurability of custom timing curves, if that is an option, can provide power and fuel economy benefits, though you have to dog deep to find the first person anecdotes.

EI systems can be self diagnostic and give positive error codes where magnetos gives you either silence or at best some roughness. I had a Bendix mag start acting rough once and replaced the condenser and points (and maybe the gear, I can't remember clearly) and it smoothed out again but I needed some help to diagnose it in the first place.

FlyEFII purports to save 7 pounds IIRC, but that's EFI too. I think magnetos are the heaviest portion of that replacement.

Many will argue for the simplicity of mechanical systems, and that is totally valid, but solid state electronics have a good record of dependability too. Moving parts or banging electrons, each has its downsides.

I think lightweight EarthX batteries have shifted the balance of redundant electronic systems too. It's easier than ever to run a backup battery with automatic failover. One thing I won't do is run a second alternator.

TTF and Zzz,

Thanks for the input. I've sent an information and pricing request to FlyEFII so I'll see what they come back with. It certainly looks to be a worthy system so I'll pursue it further. I like the idea of starting with EI and the option of adding EFI later on, but If I'm down anyway for the install, it might make sense to add it all at once, depending on the time involved.

Adding a second battery to my system will take some time and effort as well, but I agree with you Zane, with the EarthX light weights, there isn't much downside to replacing what I have now.

Blackrock, what kind of an airplane do you have? What engine do you have? Do you have a header tank? The EFII system calls for a return fuel line so if you have a header tank, that should be fairly easy to incorporate. Even if you don't have a header tank or any easy way to to deal with the return fuel, I think there's another way to accomplish the situation and I'd be glad to discuss it with you if you ever decide to move forward with the EFII system. Like I said in my previous post, my next build is going to be a Carbon Cub and I'm planning on incorporating the EFII system in that build. The Carbon Cub doesn't have a header tank but I think the fuel return situation can be accomplished by designing the fuel system so that the return fuel basically just returns back to the supply side of the electric fuel pump. It's a little difficult to describe what I have in mind here in words and a little more detailed than just returning the fuel directly to the supply side of the pump, but like I said, I'd be glad to talk to you about it if you decide to go with the EFII system and if you utilize the fuel injection aspect of it and if you don't have an easy way to deal with the return fuel.

The return fuel vs header tank design issues depends on how much heat your fuel can shed after its trip around the loop. Blackrock has an O-540, the same as I plan to use. In talking with Robert Paisley, he seems to think the return fuel to the tanks via a duplex valve is the ticket. The header tank that would be required is at least 5 gallons, and that's a lot of volume to hang in the cockpit.

Here's a few more threads where we've discussed. It doesn't mean we can't hash it out here some more though

EFI considerations:
viewtopic.php?t=16949#p242021

Fuel selector valve design:
viewtopic.php?t=17574

Zzz wrote: In talking with Robert Paisley, he seems to think the return fuel to the tanks via a duplex valve is the ticket.

This is exactly my plan. I just don't think there is any better way to do it without a largeish header tank.

The EFII looks like a good system and Robert was willing to answer my questions. I'll be using his boost pump in place of a Dukes pump on my TCM fuel injection.

whee wrote:

Zzz wrote: In talking with Robert Paisley, he seems to think the return fuel to the tanks via a duplex valve is the ticket.

This is exactly my plan. I just don't think there is any better way to do it without a largeish header tank.

Agreed, as long as you can deal with no BOTH selection.

Blackrock, sorry that hijack! We should go back to ignition discussion...

I was really hoping someone had experience with the G3i. I have been planing to use it in my build because it seems like the best option for me. The one thing I wish it had was variable timing.

Zzz,
A duplex valve and return lines back to the tanks is exactly how I have mine setup in my RV-7...and it works great. However, in my Carbon Cub build, I think I'm going to do it a little differently. Instead of circulating the fuel around the fuel rail (as the current method of doing it), I think I'll dead-head the fuel into each rail. By doing it that way there would be no "hot fuel" returning back into the fuel supply and heating anything up. You could keep all of the plumbing on the cold side of the firewall except the fuel that's being supplied to the fuel rails. You could have the two rails tied together with a fuel line on the back side of the engine joined together with a "T" and being fed by a single feed line coming out of the firewall. True, you wouldn't get the benefits of cold fresh fuel being circulated past the injectors on a continuous basis, but I think that if the fuel feed line and the fuel rails were well insulated, and considering the fact at how fast the engine is actually using the fuel, I can't see where this would be a problem...even when considering vapor lock. It surely wouldn't be any worse than a carbonated or standard aircraft fuel injected system that's being used on countless aircraft. If you were to design the fuel delivery system this way you could keep everything else on the cold side of the firewall. I plan on doing some testing to see how much heat the fuel pumps themselves make just by circulating the same fuel around and around. I think if you were to keep the fuel system and the circulating fuel on the cold side of the firewall, I believe you could get by with a very small header tank...or maybe no header tank at all. You could basically feed the return fuel that's coming out of the fuel pressure regulator directly back into the feed side of the pumps and "T" that in with the fresh fuel that's coming from the tanks. By doing it this way all you're really doing is "simulating" a header tank. If you think about how you'd be plumbing a header tank and how the fuel pumps get their fuel from the header tank and how the unused fuel is then returned to the header tank, than I think you can visualize how you could actually plumb everything together without a header tank actual being part of the system. The only way this will work though is if you dead-head the fuel into the fuel rails and not circulate that hot fuel back into the circulating part of the system. Another way I think it could be designed is by using "demand fuel pumps" that just supply steady pressure and only come on when the fuel pressure falls below a certain amount. This really wouldn't be the best setup for a vehicle due to the continuous variations in throttle and fuel demand, but in an airplane where we maintain relatively steady throttle position, I think a demand fuel pump would work just fine. With this type of a setup there would be no circulating fuel at all and you'd always have cold fresh fuel supplying the fuel rails.

Great discussion going on here; no worries about thread drift from me, I think this is right in line with the intent of the initial post although it has migrated to another system. I'm still reviewing info on the EFII so not much for me to comment on yet. G3i is still in the running, too.

Blackrock,
Yeah, this EFII topic can be fun!!...and because it's both electronic fuel injection and ignition, you never know what direction the conversation is going to go...but it's all good stuff!!