yeah it does count the number of big 'spikes' coming from a central coil and then use this to calculate the RPM. so if its low voltage going to each pencil coil which itself develops the voltage for the spark then i don't see how i can make this work.
might test it out on my charade (which i think has a central coil pack ).
the other hard part is getting it to look good on the mirror which is laminated and therefore ghosts the reflection but that is stage 2 if i get to it.
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