[TR] Coil and spark plugs polarity

[Randall]

> List:  Is it true that it doesn't matter which way one wires 
> the coil (for
> example after converting a car from positive to negative 
> ground), but it is
> important that the center electrode of the spark plug is 
> always negative?

Well, no.  Since you can't change the connections inside the coil, the polarity of the primary side is what determines the spark
polarity.

But, spark polarity makes only a tiny difference, not normally enough to notice.  Many people have gotten it backwards, and the
engine still runs "fine".  There are even engines that deliberately fire every other plug "backwards".  So, in that sense, it
doesn't matter.

Randall