Re: Pertronix Ignitor Inside Info.

[Darrel Kline <darrelk@domain.elided>]

At 11:02 PM 8/26/98 GMT, you wrote:
>Reapers,
>
>For those of you who have (or plan to get) a Pertronix Ignitor, I have some
>interesting inside information I got from one of their engineers today
>which I'll pass along.

>The problem occurs because modern electronic ignition systems don't
>necessarily have a wave form that matches the conventional breaker-points.
>With a breaker point system, the wave form present at the negative coil
>terminal rises rather rapidly as the points close, reaching a sort of
>rounded peak as the points remain closed for a period and then have a
>tapered tail as the points open and the current is broken (combined with
>the effect of the condenser).   In the case of the Pertronix Ignitor, the
>wave form is controlled by the electronics in concert with a capacitor.
>The wave form has a characteristic which includes a very sharp rise, a
>level plateau of 10 to 15 milliseconds (which duplicates the closed points)
>and a exponentially tapering tail.  With the ignitor, the voltage never is
>allowed to completely drop to zero.  Instead it hits a low of around 1.6
>volts and rises to a high or around 400 volts.  This waveform combined with
>these voltages causes the coil primary windings to saturate quickly and
>fully... much more so than breaker-points.  This is why the Ignitor is
>capable of assisting the coil in delivering much higher than normal voltage
>output (if needed).

>Hope someone found this information as interesting as I did.
>
>Regards,
>
>John

John,
I for one appreciate this information. I always like to hear what the
actual engineers say about their products. Sometimes there's just too much
speculation. 

One time I was comparing a couple of different tachometers against a
quality storage o'scope, and neither one was within 75RPM's of what the
scope read. It's pretty sad that I needed a $20K scope just to set the idle
speed accurately.

If you ever talk to him again it would be interesting to know how the
Ignitor compares to the GM HEI, and what the peak output current is. 

Does Pertronix recommend any particular coil?  There's some really hot
coils on the market now that will only work with certain ignition modules,
other modules will burn out.

Darrel Kline
Colorado Springs
1980 Scout
304 V8, Holley 2300, Crane HI6
T19 Close Ratio Transmission
Dana 300 with TeraFlex 4-1 kit
Spring-Over (Scored 1058 on Moab Off-Road's Ramp)
Custom Cross-over steering
Front Dana 44, 4.09 gears, Detroit Locker
Full Floating Rear Dana 60, 4.09 gears, Detroit Locker, Disk Brakes