Re: spark plug wires
not all outboard wires are mettalic.
actually for years it was simply cheaper.
then as we started adding electronics under the hood we started to have to use resistor plugs and resistor caps to aid in electromagnetic interference.
but for the old motor with a simple magneto metal cored wire was simply cheaper and more durable and all that was nessasary.
move up to an F350 or possibly a verado and now we have to deal with EMI or the ECU may get finicky.
most the big F yamaha motors went to a coil on plug type ign system where there are no plug wires.
automobiles tended to have radios and cassette players or like my first, a built in underdash 8 track. use of mettalic wires or non resistor plugs tended to allow the listener in that nice quiet interior to hear the ign over the speakers.
we usually dont have that issue in a boat.
so your outboard ign system most likly wont care what plug wire is used but its always easier to use what the engineer designed it with.
for testing issues carbon fiber should work ok depending on the ign system primary input and secondary output.
so no real magic just a different set of operating conditions.
