tach wiring

[general mayhem]

I have a 1976 IH 345. I replaced the prestolite ignition module with an excellent pertronix flamethrower ignition. I also bought the pertronix flamethrower coil to go with it. My problem is that the instructions that came with my sunpro tach dont list an IH 345 imagine that! My old prestolite had a white wire on it for the tach, however the previous owner hooked his tach up to the coil negative post. The pertronix ignition doesnt even have a tach wire, just a ground and a positive. So im assuming to hook my new sunpro tach wire up to the ignition coil negative post. Does this sound correct to anyone else????

 

[Robert Kenney]

So long as you use the pertronix to drive the coil directly and not through a cd box like a msd 6, hook the tach wire to the neg. Coil post.

 

[general mayhem]

Thank you Robert. Ya the pertronix is hooked directly to the ignition coil. No msd box or anything like that in there. No ballast resistor or anything. I was pretty certain that was correct, but at the price of that sunpro super tach I didnt want to find out the hard way that it wasnt. Thanks for your input its much apreciated