Pertronix ignition with Stack ST400 tach

[pooch776]

Does anyone on the forum have any experience with using a pertronix ignition with a Stack ST400 Tach? I am trying to use a ST400 tach on my Club Ford with a Bosch distributor and a 1843 pertronix module and a 3 ohm Bosch blue coil. I have never burned out a pertronix module before but I burned one out after about 5-10 min. of running with the tach pulse wire (orange) connected to the negative terminal on the coil. Are these two devices compatible with each other? Is there a resistor that needs to be added to the pulse wire for use with a Pertronix ignition? I am aware that a pertronix 1843 (black module) requires a three ohm resistance coil. Am I changing the resistance coil by adding the pulse wire to the coil. I was going to get my multimeter out and start taking some measurements but I would like to avoid burning out another module. I am going to give Stack tech support a call but I thought I would ask here if anyone has any experience first.

Thanks in advance for your help, Joe

[Jerry Kehoe]

Not sure why you are having trouble as I have used these for years with my Stack tach. I am using the pertronix coils which have the correct resistance. You might call them for some tech advice. I use the base pertronix ignitor from their advice over any of the later units. If you don't have their wiring instructions let me know as I can send one to you.

[CGOffroad]

I have had problems with the 'noise' that comes out of the Petronix mounted in a Bosch housing. Was able to remedy this on one car with resistors in line to the AIM. But, I have recently mounted a product that is offered by Veracity Racing on a 2.0L motor and have very nice results.

I recommend contacting David Ferguson at Veracity. Your question is right up his alley and you are sure to get good answers from him.

Here is some info on his products that may be a fix for your problem:
http://veracitydata.com/products/ver...cing-products/