View Full Version : Do I need a tach converter?

09-03-2003, 10:05 AM
I'm installing an MSD6-AL with a Pertronix ignitor. I've got that all wired, but not tested yet (new engine). My question is, will I need a tach adapter to drive a 1970 Mopar Tic-Toc-Tach or should I be able to hook it up to the MSD tach output? This is a rare tach and I don't want to burn it up.


09-03-2003, 11:26 AM
I have never heard of this style of tach, so I would recommend contacting the manufacture of the tach to see the type of signal it requires in order for it to operate. I know that the MSD tach output produces a 12-volt square wave with a 20% duty cycle. With some of the most common tachs this signal will work, but some of the uncommon it is not strong enough to damage a tach, it will either work or not. This is why we offer the tach adapters for a stronger signal. The PN 8910 is what you would use for your application, and the signal that is produced from the PN 8910 is a 180 to 210 volt spike peak to peak, which is what a standard inductive coil negative signal would produce.