A new test I just tried: With a wire from the negative side of the coil
to an engine ground (as directed to do by Pertronix tech support),
engine off and ignition on, I just read 7.5 volts at the positive coil
terminal. (They said to ground the coil to avoid starting the motor).
Just for fun, ignoring their advice, I took off the coil to ground wire
and tested the + coil terminal and I read 12+ volts at the terminal. Is
Pertronix correct in telling me to get a voltage reading with the coil
grounded, or is my second test correct?
I was just told that a new Pertronix Flamethrower coil should have .6
ohms resistance between its + and - terminals. Mine reads .9 ohms, 50%
higher than optimum. It's been in use for about a year.
PAW, where I get my "speed" parts, just suggested that my problem could
be caused by a weak engine to ground connection, and suggested I run an
additional engine to ground wire to be sure. To be definitive, though,
and to not get stuck on the road to Utah for SUNI this summer, I have to
get this worked out for sure. Is the correct way to read coil voltage
with the coil grounded, as stated by Pertronix (and where I now just
read 7.5 volts), or with the coil ungrounded, where I just read 12+ volts?