[TR] Electronic ignition systems

[John & Pat Donnelly]

Hmm .. the real key in determining points versus electronic modules is the
discharge of the coil primary. Points and electronic modules only trigger
"The Event", so the key to performance is how true the trigger is. 

I would be interested in seeing some scope data of the points versus the
Pertronix leading edge. I would venture to bet that the Pertronix was faster
and more consistent than points (at a constant rev), which would make it a
better than points ignition system.

While I have no data to support this, I believe when the points separate it
causes a spark and thus has some resistance to it, more than the Hall
Effects in electronic modules. That resistance may slow down the discharge
process and could cause issues at higher revs. Where that number is is a
good question.

Pertronix's reliability is also still a question though in my mind, so by
default a working unit is better than a non-working one!

Johnnie
'67 TR4A with points.


> > I can accept that a perfectly set-up ignition module has the car
> > running
> > better than perfectly well set-up points,
> 
> IMO, that actually doesn't happen; at least not to any measurable
> extent.
> With the Pertronix, XR-700 and similar devices; the energy delivered
> the
> spark plug is determined by the coil, not by the module.  All the
> module
> does is provide "perfect" points continuously, rather than the constant
> degradation of mechanical points (plus whatever timing error is caused
> by
> shaft wobble and consequent changes in point gap).