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Electronic ignition race performance ?

N360DF

Member
Gents I was little surprised in a mall conversations I have with Lycon.
In the subject EI they stated they only use mags on the high performance builds.
Including the race engines.

This confused me pretty much!

Best regards
 
A race is at WOT and pretty constant conditions.

You can set the ignition advance for the conditions of the day.
 
Ok I see... good point! But what about the other benefits ?
Better spark etc. ?

I also more or less find the suppliers brag about the winner planes ?

A race is at WOT and pretty constant conditions.

You can set the ignition advance for the conditions of the day.
 
The primary benefit of electronic ignition is the ability to more efficiently run lean of peak at altitude. This is due to longer duration spark and ability to adjust spark advance in flight. The CAFE Foundation reports higher horsepower with magnetos. Ref. their three reports on electronic ignition, interesting reading.
 
Well, that depends...

You can see DA at Reno of 7000’ at times, and 4000’ on other days. So, a bit of twizzling with the mag lead would be beneficial on a NA engine. The electronic setup would do that for you.

Of course the turbo’d ships would not be affected too much - keep in mind the Lancair that won was at ~100”MP, with spray bars doing their thing and ADI helping out...again, on that particular plane, the whole setup was electronic, so it might have been a bit easier on the pilot - but the workload is still high.

So, it depends...look at the DA and proceed from there (if you have mags and a NA engine).
 
Depends on the "race"...

If you are talking about an engine opperating at rich mixtures and fat air, then its relatively easy to light the mixture - there will be little performance difference between a properly timed and maintained magneto and a comparable EI. In this case, the EI's benefit is the ease of tuning on the fly to match conditions (assuming the EI vendor offers this benefit - not many do).
 
Lycon builds some great stuff but needs to move into the 20th century with regards to views on ignition systems.

SDS supplies the EFI and ignition for the 2 time Reno Sport Class champion Andy Findlay. His Super Legacy did a 402 mph race average and a 409mph lap in 2018 with straight line speeds near 430 mph from the telemetry, running over 95 inches. The proof is in the pudding. The SDS EFI and EI allows Andy to get maximum power and reliability from this very highly stressed engine.

As far as I am aware. This is the fastest piston powered Lancair Legacy in the world. No magnetos in sight. Kind of hard to argue with that...
 

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Another thought-----if the race rules allow NOX, the ability to alter the timing and mixture when you push the button is kinda nice;)
 
The primary benefit of electronic ignition is the ability to more efficiently run lean of peak at altitude. This is due to longer duration spark and ability to adjust spark advance in flight. The CAFE Foundation reports higher horsepower with magnetos. Ref. their three reports on electronic ignition, interesting reading.

By my read of their report, there wasn't an exact apples-to-apples comparison. The cases where the report shows dual mags giving more horsepower/speed are ones where they left the timing of the EI fixed (at 41, 36, and 30 degrees) while the mags naturally stayed at 25 degrees throughout. Seems like the mags' "advantage" in this case was having more optimum timing for those rich conditions vs. the timing the EI was fixed at.

I think more interesting would be comparisons of mags vs. dual EI fixed at 25, and mags vs. dual EI with a fully-optimized timing curve. I'd expect the EI would show a clear advantage in cases outside those where 25 degrees is about the optimum timing point (edit: and very close performance between the two at that 25 degree optimum point, especially with rich mixture and thick air, as Toobuilder notes).
 
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By my read of their report, there wasn't an exact apples-to-apples comparison. The cases where the report shows dual mags giving more horsepower/speed are ones where they left the timing of the EI fixed (at 41, 36, and 30 degrees) while the mags naturally stayed at 25 degrees throughout. Seems like the mags' "advantage" in this case was having more optimum timing for those rich conditions vs. the timing the EI was fixed at.

I think more interesting would be comparisons of mags vs. dual EI fixed at 25, and mags vs. dual EI with a fully-optimized timing curve. I'd expect the EI would show a clear advantage in cases outside those where 25 degrees is about the optimum timing point.

I am agree!
 
The bigger advantage of EI over mags is clearly the variable timing with MAP and at least with SDS, the LOP advance settings. We can see in flight testing, 2-4 knots come back to us on RVs with the LOP advance feature.

We can retard timing a bit at high MAP to avoid detonation and high CHTs during takeoff and climb, while still having full advance for optimal power and economy in cruise. This is even of more benefit for those burning lower octane mogas.

Fixed timing mags are a compromise. They can't hope to match the economy and other advantages that variable timing offers.
 
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