Have you installed an aftermarket ECU in your pre 1995 car and noticed that the tacho signal output from your ECU is not able to drive your cars stock cluster tacho. Or changed your ignition system and its output is also giving you the same problem, the stock tacho is just not working. Well the reason is because in pre 1997 vehicles the stock tacho’s on cars used a much higher voltage to drive them than what an aftermarket ECU or replacement ignition system can output. The output from aftermarket ECU’s and most replacement ignition systems will be either a 5v or 12v square wave pulse and is just not enough volts to drive these older 24V & back EMF style factory tachos.
This is where these little JRP tacho booster signal adapters come in, you are able to feed the 5v or 12v output from your aftermarket ECU or ignition system, and these little boosters will convert this low voltage pulse signal to a high voltage signal which will drive the old factory tacho in your car. These little converters will output at least 48v and are capable of giving you a stable high voltage tacho signal that will drive any old stock cluster tachos.
Now as we mentioned on our Tach Adapter page, these units can also be used in parallel with the Tach Adapters to get stock clusters working when you have done an engine swap. For example, you have done a LS swap into an old Supra for example, and you just can’t get a signal from the LS that will drive the stock cluster tacho. In this case you would use the tach adapter to first pull a 5v or 12v square wave tach signal from the LS motor, then run that signal into these little tacho boosters and run the output to the stock cluster and bingo, you have a stock cluster tacho working again.