to pertronix? i talked to one of their reps at SEMA last week and apparently it's not unusual for the tach to not work correctly after installing the ignitor. he said there were several steps to check in order to get it working. but i figured i can't be the only guy here who's installed pertronix, so i'm probably not the only guy here that has had tach problems. if you've had this problem and corrected it, could you please let me know what you had to do to fix it? TIA

I don't know what year Z you have, but the early ones had tachs that used an inductive pick-up. Basically it is a loop of wire through metal loop on the tach. This wire is basically the conductor between the coil and the points. Now with the conversion to electronic ignition the points, if still used to trigger the ignition, has a fraction of the current flowing through them than they used to. It's not enough current to drive the tach.

I did the conversion to '72 just after I bought it new with a heathkit unit. It turned out the points current was now one tenth of what it used to be. I found some small diameter wire and replaced the single loop at the back of the tach with ten loops. It worked just fine then.

I'm not sure of how the Pertronix system works, but if it still uses your old points, you could do what I did. If it uses optical or inductve pick-up to trigger the system, I don't know what to suggest. I know others have said to go to a later style tach, but I wouldn't want to do that if I didn't have to. Perhaps Pertronix has some suggestions if you talk to someone with a technical background.

Try searching the site for "Pertronix tach" I came up with this thread:

http://www.classiczcars.com/forums/showthread.php?t=8848&highlight=pertronix+tach

an insane amount of people have complained about the same problem with the Pertronix kit and the stock tach. I switched to pertronix myself, and I have never had a problem with the tach not working/reading correctly. Check out the pertronix article on www.zhome.com for correct wiring.