28+ 1965 Mustang Rally Pac Wiring. Our rally pac tach connects directly to the negative side of the ignition coil (whereas the original rally pac tach connected to the ignition system). Other than power for the lights and clock, the only wiring for the factory rally pac was a connection to the ignition ballast resistor.

Almost any other tach is not wired the same way but uses a wire going directly to the coil in parallel. No problem with the clock, the tachometer install sheet states that there must be ballast resistor. I am trying to install a mustang “rally pac” tachometer and clock on my 65.




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