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Tips
Tips

Coil connections

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Hi Velo,
I bought a Smiths voltmeter off Ebay. It doesn’t match the other gauges exactly. I just tapped into a white wire coming off the ignition switch (not the looped one from the tach. to the coil)
As far as wiring the Pertronix, if you are looking for the original wiring diagram, try HERE . This is for positive ground.
 
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Yes Velo, you have an extra two wires. The white wire from the ignition switch and the black one from the Pertronix module. So just add a male lucar connector to the Pertronix black wire and connect the two together.---Fwiw--Keoke
 
As I remember from the wiring diagram, the power to the coil runs from the starter switch, through the tach, to the positive lead on the coil. (SW lead for old positive ground, and CB lead on old coils, with negative ground conversion.) I don't see how this should change the tach. But I'm not much into electronics, so a different opinion would be gratefully accepted.000000000000000
 
Take it on faith, that the polarity of the pulse being fed to the "Electronic" tach driven off the ignition system must be reversed if you reverse the ground system polarity in the car.---Keoke
 
Keoke,

Any way that you can reach through my laptop, if I set it close enough to my Healey and tune the carbs as well?

Thanks for the tips once again!
 
Here's the way I see it: One side of the primary coil must be fed by the white wire from the tach. That's what provides power to the coil. That's the same side that the red Pertronix wire from the distributor also connects. The other primary side of the coil is connected to the black wire from the Pertronix module coming from the distributor, and the white and black wire going to the kill switch, operated at the battery cut-off switch in the boot. On the BJ8 harness is another white pig-tail that without Pertronix would have been connected to the distributor points, at the side of the distributor. With the Pertronix ingnition, this wire is surpfluous. As far as polarity is concerned, that's a subject of debate elsewhere. But I chose to use an older, Lucas coil, with the SW and CB connectors, which in a positive ground scenario SW= negative, and CB= positive. I opted for negative ground, and chose to reverse this, with SW = positive and CB = negative. This configuration does work.
 
Hi Velo,
Is your car positive ground as original? One thing that may be confusing is the two wires on the pertronix are different colors between the positive and negative versions. The pos. ground ignitor has a black and a black/white wire. The neg. ground version has a black and a red wire.
 
Yes of course that works Cutlass,but only on a negative ground car using a negative ground Pertronix Module---Keoke
 
Keoke,

My car was converted from Positive ground to Neg. ground before I purchased it a few years ago. I had my local British car guru install the Pertonix as I could never seem to get it to work. So the pos to neg thing makes me even more confused!
 
Naw don't be confused. The Pertronix module for the Negative ground application has red and black wires.Simply connect the red wire to the same terminal on the coil as the +12V white wire connects to [+ or CB ] depending on the coil. The black wire simply connects to opposite terminal. The previous short wire that connected to the Lucar terminal on the distributor is no longer required.---Keoke
 
Keoke's right, as usual. For those contemplating a Pertronix unit, just be sure to buy the one for the polarity you use for the rest of the car. If you do that, the instructions that come with the unit are very clear. Seems to me that the confusion arises with the labeling on the old coils. CB, which means contact breaker, is positive on the old coils. SW, which means switch, is negative in the old coils. So in a negative ground conversion, common wisdom calls for connecting your negative leads to the SW coil connection, and the positive leads to the CB coil connection. If the coil is labled + amd -, then rely on those designations. Maybe that helps. (Note - there are those that say that a coil is just a transformer, and doesn't care which way the electrons are flowing in the primary coils. I don't know. But if it doesn't matter, I choose to hook it up according to common whisdom, detailed above.)
 
Well Cutlass, its true the coil is just a transformer that doesn't care which way you choose to make the "electrons" flow. It is the Sparking Plug that wants a negative spark so it doesn't have to work so hard.---Keoke
 
I'll take your word for it. Many things are beyond my understanding, and I'm happy to take the word of others who really do understand. I get in trouble when I think I know more than I really do.
 
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