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-   -   Lycoming New Electronic Mag Osh 2019 (https://vansairforce.net/community/showthread.php?t=173730)

Toobuilder 04-27-2020 05:00 PM

Quote:

Originally Posted by 71459 (Post 1425764)
The phrase "advanced timing" used here means the system is retarding (not advancing) the timing with decreased manifold pressure. Right?

If it is said that the system is providing "advanced timing" with lower power, one would read that to mean it advances the timing, when apparently it's doing exactly the opposite of that.


In this context, lower MP/ higher altitude advances the timing compared to a fixed magneto. So yes, "advanced timing" means exactly that - the plug is firing earlier in the piston stroke/crank rotation.

Don E 04-27-2020 05:51 PM

Confusing throttle with MP
 
Quote:

Originally Posted by 71459 (Post 1425764)
The phrase "advanced timing" used here means the system is retarding (not advancing) the timing with decreased manifold pressure. Right?

If it is said that the system is providing "advanced timing" with lower power, one would read that to mean it advances the timing, when apparently it's doing exactly the opposite of that.

Jon,
I think you?re confusing throttle and MP. During cruise at 10,000? with wide open throttle and leaned out, my manifold pressure is low and even with high rpms my power output is below 60%. This is an example of where the ignition advance lives. Ignition is not retarded, it is advanced. At altitude, in cruise, leaned out is where you get the advantage of the ignition advance. As others have stated, other benefits of EI include easier starting and smoother idling.

YellowJacket RV9 04-28-2020 03:59 PM

Finished installing my Surefly today. Longest part of the install was getting a cotter key on the mag gear to my satisfaction. It comes with one - I was lucky to have a bag of 25 of them. Funny how the shortest items in the instruction manual usually take the longest.

Anyways, I was immediately impressed at how quickly it started, both cold and hot. It really is like starting a car. Idles smoothly much lower and I can lean it much farther on the ground. I am in fixed timing mode for now, so not sure how much the efficiency will change, but I will probably experiment with the variable timing mode eventually. I also had to move my one EIS tach input to the right magneto, but that was an easy fix.

Chris


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