I haven't been following this thread in detail, but I have a few questions and a comment:
I certainly agree that the ability to increase spark advance at low manifold pressures gives a substantial improvement in efficiency. But how much improvement does a single electronic ignition give compared to a dual system? The only answer I've been given is "about half." That makes sense, I suppose, but is there any data out there to support that? Most of my long flights are at about 12,000 feet, so I expect some improvement over dual mags.
Second question: I have disconnected the MAP sensor from the intake
manifold port, leaving it to read atmospheric pressure. I can't see any real difference in operation, since almost all cruising is done at full throttle with manifold pressure about the same as atmospheric. The advantage is noticed during the runup - the rpm drops are about the same, whereas with the MAP sensor connected the rpm drop when shutting off the mag was very small, making it a little less of an obvious test. Are other people running electronic ignitions with the MAP sensor disconnected? The only disadvantage I can see is if you fly a lot of the time at low altitudes and part throttle you will lose some of the advantage.
Finally the comment (with a question buried in it): Several, including Bill (message below) mention the advantage as being fuel flow reduction. But at full throttle cruise I can't see how fuel flow could be reduced, only
power increased. Do people fly at a fixed airspeed, throttling back or reducing rpm to save fuel? Another advantage is that LOP operation could be smoother on account of the extra spark advance, but I've never done a back-to-back comparison to verify that.
I really like the E-mag concept and the new 6-cylinder version would be very nice. But they are handicapping themselves by trying to get the full dual system into a single package. I was told that they are trying to replace the "dual" Bendix mag and I agree with their reasoning, but it makes the development more complex. Another comment - they, in the same package, are implementing a different (non-inductive) method of creating the spark. At OSH they wouldn't talk about the technology. I suspect that is another reason for the delay.
Gary
Yes, it's frustrating. I've been waiting for my 6 cylinder E-Mags for well over a year. HOWEVER, every time I talk to them they are extremely clear that they have not set a date for release. Only when I really press them will they give me their "guess". They make sure to say that their guesses are usually wrong and that they are not promises or schedules. Actually, I find it a bit refreshing compared to some of the "it'll ship next week"
promises that I've heard from other manufacturers.
I've been using their 4 cylinder product on our 320 for a little over 500 hours. I have found it to be more dependable and far more efficient than a standard magneto. At the same true airspeed I save almost 1 gallon per hour (160 hp stock Lyc O-320) over a magneto. This fuel savings has easily paid for the ignition system. If this same efficiency and dependability carries over to the Continental 6 cylinder, I can't imagine any reason not to install it.
I have no connection to E-Mag, financial or otherwise, and am passing on this information only as a report of the results that I have had with their product.
Bill Harrelson