TR2/3/3A TR3 Static Timing with Pertronix Ignition

[MGTF1250Dave]

Aloha,

I checked my ignition timing after I recently installed a Pertronix Ignitor ignition system using the static method. I found the following information on the forum written by TR3 Driver (Randall) and DKLawson (Doug Lawson).

"You should be able to check it with the engine not running : Fully connect the Pertronix module, coil, etc.; then connect a test light from the negative side of the coil to ground. With the key on (power to the coil & Pertronix), the test light will come on when the virtual points open.

FWIW, I'm reasonably certain that only applies if the coil is wired up, and the "points" are closed. It's the main power transistor that overheats and burns out, due to the current through it and the coil. Pertronix is distressingly vague about this" ... (TR3Driver)

"You are correct. The issue is that when the coil is in the circuit and the Pertonix is powered, around 4 Amps is flowing continuously through the module and it overheats. In normal running the duty cycle is reduced so overheating is not a problem.

You can indeed static time Pertronix. My method is to have the system hooked up "as normal" and put the test lamp between coil (-) and an earth point. When Pertronix "opens" the light will come on, just like when you are using points. Rather than running back and forth to the ignition switch to limit the "on" time of the Pertronix module... I simply unplug its red wire which is connected to my coil (+) terminal since I do not have a ballasted ignition system." (Doug Lawson)

I used the same procedure to get started as if the stock contact breaker point system was installed and set up the test light as Randall and Doug instructed. I used my installed battery cut out switch to keep the Pertronix module from over heating, limiting power to it to about 5 seconds. I'm not sure how long is too long so I tried to make it as short as possible. I would then rotate the distributor CCW until the light came on to find the point of ignition. With points you would do this and then go CW until the light went out to set the distributor. My experience was that once the test light came on it would stay on even after rotating the distributor CW back to the starting point. Only after I disconnected the battery would the light go out, the ignition switch was on to power the coil and Pertronix during the test/adjustment. So, I decided to just rotate the distributor CCW until the light came on and lock down the distributor there. It seems to have work fine.

So the good news is I got good advice from the forum, I didn't burn up my Pertronix setting ignition timing, and the car runs fine.

 

[dklawson]

Imagine my surprise seeing that I have been quoted. Thank you. I'm glad that the discussion Randall and I had helped.

I have been told by those who have called Pertronix tech support that "too long" is 5 minutes. To be safe, I make sure I limit myself to 3 minutes and always pull the Pertronix red wire when I don't need the module powered.

 

[MGTF1250Dave]

Aloha Doug,

Thanks for clarifying the "too long" time frame. I was reasonably sure I was being over cautious, but I didn't want to fry it setting the timing.

 

[TR3driver]

I think this may have gotten lost in the discussion and quotes above. I'm reasonably certain that you can safely leave the ignition on as long as you want while setting the static timing, IF you use your test lamp as a dummy load instead of the coil. IOW, leave the black wire off the coil, and connect your test lamp from the black wire to the red wire (or between the black wire and coil terminal, if that's easier). That also means the light will go off when the "points" open, so now the procedure is to rotate the dizzy CCW until the light comes on, then back CW until the light just goes off.

 

[MGTF1250Dave]

Aloha Randall,

Thanks for clearing that up for me. I was concerned when the light would not go out like it dose with points. I find the test light going on or off helps me more accurately set the distributor timing. I like the set up you described. With that I can now be more precise in determining where the switch goes "on" or "off".

 

[dklawson]

I agree with Randall. If you connect your test lamp between the Pertronix black wire (negative ground cars) and a 12V source, the light will be on when the Pertronix is "on" (equivalent to points closed) and the light will be off when the Pertronix is "off" (equivalent to points open). The test lamp will only require about 90 mA to power and shouldn't cause significant heating of the module.