[TR] Coil and spark plugs polarity

[Geo Hahn]

On Sun, Nov 9, 2014 at 7:28 AM, Andrew Uprichard <auprichard at uprichard.net>
wrote:

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)...



Though spark polarity may be of little import -- it has always been my
understanding that coil polarity needs to be correct for the polarity of
the car.

IOW, on a positive ground car the little (white/black) wire from the coil
to the distributor should be connected to the coil post marked '+'.  Easy
to remember if you think about how that feed is an intermittent ground
(interrupted each time the points open).

Earlier coils were marked CB (contact breaker) and SW (switch) but as far
as I know those marks were made with positive ground cars in mind so
'CB'='+' and 'SW'='-'.

The ignition will still work with coil polarity reversed but I think the
points will not last as long.

OTOH, maybe this is just an old mechanics' wives tale that I believed and
am repeating.

Geo