I have installed a MSD Ignition and Distributor in my 80 Vette and now the tach does not work. Any suggestions on getting it working again?

Thanks

The MSD like 99% of all aftermarket ignition boxes have a tack wire output that puts out a 12V square wave signal. Most new cars use the same type signal. What you need to make your take work is to install a MSD tach Signal Amplifier or Tach Adapter depending on how your are triggering your system.

Call their tech line or go to their website and read their technical section and look at part numbers
8910
8910-EIS
8920

Depending on how you have the system installed will decide which piece you are going to need.

They also mention in their catalog that on GM Factory Tachs that you just need to by-pass the in-line filter and it will work.

It will be one of the things above to correct.

Thanks for the info. I shall give it a try over the next few days