Solid wire ignition

field

if the wire is point to point straight the voltage builds and the spark starts and there is a flow of current
you have a field in concentric circles around the wire while the current flows and its size and density is based totally on the current that flows
i.e how much energy there is per unit of charge passing that point in a unit of time

The magnetic field around a current-carrying wire - Magnets and magnetic fields - Edexcel - GCSE Physics (Single Science) Revision - Edexcel - BBC Bitesize.


if the wire is coiled

I'd guess the system acts more like a solenoid and the field of each wire loop combines to make a bigger field. so a spiral wound ignition lead will ostensibly have a North and South magnetic pole for a split second each spark.

both will throw out a magnetic field from the ignition lead. size and orientation will differ for each configuration in the casing of the lead.

hard edges are "hammered off" that field, by suppressor cap or inbuilt resistance of the lead

if you can keep the sparks inside the cable, an engine will run with household copper or flat battery jump lead as an ignition lead

might not be ideal but it shouldn't kill the ignition module

it might however cause havoc on a modern car with a true computer controlled motor by messing up signals from crank and cam triggers, which usually come from magnetic triggers connected using shielded coax with a data rate way higher than the pulses from your dizzy pickup. that coax cable can only shield so much. its just a wrap of plastic coated tin foil between the central wires and the case..

8 big pulses from a mopar dizzy per 4 stroke cycle...

36 (-1) pulses per revolution of the crank from an FORD EDIS crank sensor pickup, one of which has to be missing to give TDC, any others missing and eventually after a few more cycles, it's assessment of where TDC actually is starts to drift. limp home mode initialised

i know which one is more likely to be messed up...


Dave