<VV> ignition (coil) voltage

[larry@forman.net]

On Wed, 3 Mar 2004 17:49:10 -0500, "kovacsmk" wrote:
>  I noticed a query about ignition voltage in the last VV and this
> afternoon just coincidentally I installed Petronix ll and 40K coil in my
> '66 4 dr. The voltage suggested for this set up is full 12, bypassing or
> paralleling the resistance wire. When I checked the voltage at the coil
> + terminal with the ignition on and engine not running, I read 11.9V.
> Running engine the voltage goes up to the battery/alternator voltage of
> 13.5V. I think is OK not to bypass the resistance wire in this case as
> the voltage to the coil is at least 12V. Looks like the resistance wire
> is not doing much in this car. (The wiring harness is all original with
> the obvious resistance wire in place)
>  Any comments??
> Getting all the information is most of the solution.
> MIKE KOVACS

Hi Mike,
You had the "points" open, really the Ignitor's hall effect and driving circuit was not conducting so the circuit was open and not drawing
any current.  This is to be expected, since the Ignitor I often runs about 24 degrees of dwell out of the 60 degrees per cylinder, thus you
have a better chance of not drawing any current when the engine is stopped and the ignition switch is ON.  You could have either rotated the
engine slightly or tried to rotate the distributor rotor and you might have dropped some voltage as the negative terminal was grounded or
close to zero volts as the Ignitor circuits essentially closed the circuit like the points would normally do.  With a resistance wire or
ballast in there, you might see somewhere between about 6 and 9 volts on the positive terminal of the ignition coil.  If you have the
ballast bypassed, then it should read close to battery voltage for any condition, when the ignition switch in ON, and all the voltage drop
will be essentially across the coil and little through the Ignitor switching circuits.
-- Larry

Larry Forman