OER BP1105S Features:

Reproduction of the original hood tachometer 8000 RPM with 5000 RPM red line found on 1970-72 Buick Skylark, GS and GS 455 models. Each tachometer is manufactured to original factory specifications and includes the wire harness offering an authentic appearance and fit. Each tachometer is manufactured with a tightly sealed case to keep moisture out, which means less corrosion of internal parts and long lasting dependability. The biggest problem was they built up condensation inside the tach, causing the movement to fail. This tachometer will also accept factory heater vacuum hose to tach. GM's fix was to connect a vacuum hose to the bottom of the tach to the heater box on the firewall. What this allowed was to keep warm air blowing into the tach at all times. A few quality points: Has clear glass lens: Accepts factory GM tach harness: Top and bottom are screwed together like factory: 100% like original in fit and finish: Can be connected to the dash light to be dimmed: Made in the USA. Replaces the original exactly. Tachometers will work with factory GM points or factory HEI ignition. When using an aftermarket ignition system likes MSD, Accel, Patronix, ect. A lot of these systems generates higher output voltage to the tach lead than what a factory GM tach can handle. Factory GM tachs can operate on voltage ranging from 11.2 to 14.7 Most aftermarket ignition systems generate over 18 volts. You will need to buy from the manufacture of your ignition system an adapter to lower the voltage to the GM factory voltage. Made in USA

Tachometer Note:

• Only Compatible with factory ignition systems
• When using an aftermarket ignition system such as MSD, Accel, or Pertronix, an adapter must be purchased from the ignition manufacturer
• Many aftermarket ignition systems produce over 18 V at the tach lead, while OEM tachometers are designed to operate between 11.2 V and 14.7 V
• Always use a proper tach adapter to reduce voltage to the correct range and prevent tachometer damage