What will happen if coil wires are reversed? Ford Focus coils go on spark plugs today... $6 each shipped new.

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DreamV4

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I believe, nothing will happen, spark can fly in either direction. Just want to know what smart people think about it.
 

02GF74

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There are plans on the Internet to make a fly powered airplane , you basically super-glue flies onto the wings.
Screenshot_20210802-222325.jpg

I'll leave it to DreamV4 to tell us how much torque they are producing.
 

02GF74

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I believe, nothing will happen, spark can fly in either direction. Just want to know what smart people think about it.

What exactly do you mean by nothing will happen?

Bearing in mind that the primary and secondary coils share a common connection, which is usually ground, see diagram below. So if you plan to swap the wires on the input, you are effectively grounding the driver, so, yes, as far as spark generation goes, nothing will happen but the driver is likely to release smoke.
View attachment 78637
 

DreamV4

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What exactly do you mean by nothing will happen?

Bearing in mind that the primary and secondary coils share a common connection, which is usually ground, see diagram below. So if you plan to swap the wires on the input, you are effectively grounding the driver, so, yes, as far as spark generation goes, nothing will happen but the driver is likely to release smoke.
View attachment 78637
Thanks, I'll check bike and Focus diagrams before installing, I have connectors.
spark.jpg
 
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02GF74

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Not sure what happened there but I edited all that out ad ts not 100% incorrect.

Providing the coil pack does not have a connection to earth, (for example the outer metal can on old style car ignition coils) the input wires can be reversed, the result being spark is negative instead of positive.

Trawling the net is inconclusive. Some say engine runs well, others not. The only reason for this I came across was since the spark jumps from positive to earth, the central electrode is a much smaller area than the L shaped earth tab so it's place of origin will be consistent.

I seem to recall the ford edis coil pack uses wasted spark does not have the secondary connected to primary but to the plugs, so one spark is positive going, the other negative.

So the answer is it should work, but it's just a matter of swapping the 2 wires over so why not use it like the way the engineers intended?
 

one2dmax

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We have wired up COP's both ways with no discernable difference though we do go ahead and wire them normally lol.
 

desert_max

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A coil is a coil.

(Unless there's a diode across it - which is not typically an application found in automotive ignitions that I know of).
 

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