Our kits will work without one, but the engine runs better with a speed sensor installed. Our sensors attach where the speedometer cable attaches at the transmission. Some kits can also use the existing dash speed sensor, or can be connected to the two-wire speed sensor in the later transmissions. Late GM pickups and some cars use a 40-tooth reluctor wheel sensor which won't work with earlier fuel injection systems. Check with our Tech Department for information on your specific application.
Voltmeters are much easier to install.
Ammeters require large gauge wire and most older ammeters don't have enough amperage range to operate safely with modern high-output alternators. A voltmeter is hooked up as easily as a light bulb, and gives a very accurate indication of your charging system condition. It connects to the main post on the back of the alternator.