IMHO (based on dyno and operational experience) hotter, longer and more energy spark claims have no direct impact on performance assuming you are comparing them to an ignition system that is operating within specifications on an engine which is also operating within specifications. What hotter, longer and more does give you is more MARGIN for situations where you are too lean, too rich, close to fouling, cold starting, etc.  Think of it this way, if the spark plug "lights the fuse" on the combustion process will the explosion be any bigger if it is started with a match or a blow torch?

Once you put the requisite 140 mJ (more or less) into the mixture the combustion process has started and, like being a "little pregnant",  adding additional energy won't get it "more started".

Brent, et al,

 

Interesting.  Of course, the developers of SlickSTART must have seen the same thing and were convinced they could even sell people a device to overcome the failings in their weak-kneed mags and the irresponsible actions or inactions of the person operating the starter button.  I know in my wee engine, the mixture that meets its match isn't always perfect - luckily the blowtorch always finds the mark hidden somewhere in the dark dank chamber of horrors.  Wait, LSE only promises in excess of 120 mJ.  I have been led astray again.  Or, maybe not, SlickSTART raises the peak mJ from 51 for the single impulse-coupled mag to 255 during the start.

 

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Aircraft engines have dual ignition systems for increased detonation margins, NOT for reliability from redundancy. Aircraft combustion chambers are so freaking big that by the time a flame front has traversed the chamber the remaining gas has been compressed and heated to the point of detonation.  Starting the fire in two places shortens the combustion time significantly and reduces the opportunity for detonation.

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Exactly!  Of course, this is also interesting when the matches are lit at wildly different times such as when one is advanced whilst the other is fixed.

 

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This is also the mechanism for the RPM drop during a mag check.  When you turn off one mag the combustion event takes longer which has a similar effect as starting the process later, AKA "retarding the timing".  So when you turn off one of the mags during a ramp check you may think the engine is slowing down because you are adding less spark energy but what is really happening is that you are changing the timing and anyone who has adjusted the timing on a car knows that timing changes result in RPM changes at low power settings.
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Hmmm....  Interesting effect when using an EI, there is no noticeable drop in RPM on my engine when turning one ignition off.   Of course, there is a big drop when I turn off both.  Anyway, it is a timing puzzlement because I think I see about 25-27 degrees BTDC at 1800-1900 RPM during the simulated mag check.  I will remind my self to note the MAP and RPM along with the timing readout next run up.

 

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My concern with most aftermarket ignition systems is an apparent lack of robustness. The use of remote "brain boxes" with D-Sub connectors; the lack of demonstrated lightning, EMI, HIRF protection; exposed crank sensors that are vulnerable to bird strike, belt failures, accidental damage all make me apprehensive of the failure of this critical system.

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I certainly agree with your distrust of D-Sub connectors for this application and my own experience supports their inappropriateness.  LASAR utilizes nice flat pin locking connectors worthy of use on the Shuttle.  Now, about the lightning - I thought only Lancair IV's got hit with lightning.  Personally, I avoid lightning like the plague as both are potentially more life threatening than sticking a knife in the toaster to get that last burned piece of bread.  EMI/HIRF - I don't know, I see (hear) no interference (no, my head is not a scientific sensor) - nothing to compare to the disruption of temp sensors noted during radio transmissions over the Garmin 430. 

 

Unless the bird started in the engine compartment or the engine is mounted EZ style (backwards), there is little chance of it getting behind a Lycoming flywheel where many Hall effect pickups are located.  In my airplane a belt failure only allows the alternator to wind down. Accidental damage could occur if a passenger with size twelve pointy toed shoes kicks the "brain" - Oh, that's right, the other one is safely mounted in a secret undisclosed location. 

 

I know my reply is smart-alecky and not liable to address your concerns.  But, we are all taking a calculated risk, starting with the trip to the airfield, by flying in a little airplane personally built in a garage following the Lancair Construction Manual. 

 

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Given that there is an "ignition delay" between the static timing and the actual plug firing, that this delay is different for mags and EI and that simultaneous firing is important to detonation margin, how do you know the EI and mag are firing at the same time?
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Exactly!  For a NA IO 320 or 360 operating at middle altitudes and 75% power, the timing I have read about or seen is pretty close to 25 degrees, the same as a mag.  However, at low power settings (higher altitudes), where the EI may be operating with as much as 42 degrees advance and the mag is still at 25, there is a significant discrepancy.  Fortunately, low power settings increases the detonation margin.

 

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What really scares me is the availability of  builder programmable (adjustable) timing advance characteristics.  You might as well bring him to the rim of the Grand Canyon, blindfold the poor bastard and tell him to walk around until he finds a high spot.  The gains are small and the hazards are deep since a "holed" piston WILL ruin your day. Timing curves can only be developed by knowledgeable individuals using a properly equipped dynamometer. The GAMI or Barrett facilities are good examples.
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I don't know about the rest of the EI producers, but LSE is very responsible and honest.  The following phrase is printed in the manual:

 

 

I was thinking of installing the timing controls and posting the above statement as a placard over the controls. Maybe a picture of the Grand Canyon would suffice - It sure would improve the artwork in my airplane.

 

Brent, I share your love of technology and your respect of good old reliable magnetos.  I started my adult life by programming vacuum tube computers.  Impressed with the switch to transistors, I did note that the old brass mechanical tide table computer was still better than those newfangled internally programmed ones.  Today I am sitting in front of a machine unimaginable in the 60's.  I am a technology junkie ready to take chances with the future since there is so little time, so much to do.........  But I wander.  Well, time for my meds before they strap me back in bed.