Dual electronic ignition on single module

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Prescott Valley
The normal electronic ignition system most of us use (HAPI/GPASC) has a hall effect ignition module that operates two dual-fire coils timed 180 degrees apart. The coils have 3 ohms of primary resistance. My project engine has this fixed-timing secondary ignition in conjunction with a Slick magneto. Now I am just brainstorming here... If I wanted to use the single secondary ignition module to fire all 8 spark plugs and leave the big heavy magneto home, could I replace my two coils with four 1.5 ohm dual-spark coils? I realize that I would need to develop a means of advancing and retarding the timing on the module. The question here is: Would the ignition module handle the job and would the coils function properly when paired in series (two coils for the back cylinders and two coils for the front cylinders)? I don't really need a lecture on why I should not give up the magneto and I do realize that the ignition module would be a single point of failure. I'm just looking for someone who really understands electronic ignition systems. Can I run two 1.5 ohm coils with the primary windings in series triggered by an ignition module designed for 3 ohm coils? Is there any degradation in performance or reliability?
 

Toobuilder

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The SDS CPI brain box will fire a pair of 4 tower coils. The box also has all the advance, start retard, and programming functions built right in. And serves as a limited engine montitor, showing RPM, MAP, Voltage, advance, and a bunch of other stuff.

Buy the brain and hall sensor from Ross and the rest from Amazon. Does not get much simpler
 

TiPi

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I would put the coils in parallel, that way you would have some redundancy if one coil fails and less likely interference from one coil on the other. The big question is if your trigger module can handle the extra current (double) or you might need to go to higher Ohm coils.
 
Joined
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I would put the coils in parallel, that way you would have some redundancy if one coil fails and less likely interference from one coil on the other. The big question is if your trigger module can handle the extra current (double) or you might need to go to higher Ohm coils.
My concern is that putting the primary windings in parallel would double the amperage through the ignition module. I don't know if it can handle the extra load.
 
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