Tach Adapter

The AMP EFI AXM-100 High Voltage Tach Adapter is engineered to resolve compatibility issues between modern engine management systems and classic tachometers. Many tachometers from the 1970s and earlier rely on the high-voltage spike generated by the negative terminal of an ignition coil, a signal type not directly provided by many contemporary ECUs, such as MS3Pro, MicroSquirt, or MSPNP Gen 2. The AXM-100 effectively translates the 0-12V or 0-5V square wave tach output from these modern ECUs into the high-voltage, coil-equivalent spikes that older analog tachs require. This adapter is suitable for a range of classic vehicles, including American muscle cars from the 1960s-1970s, European classics up to the 1970s, and many 1980s and some 1990s Japanese cars, with a particular mention of Toyota models. The unit features an Amphenol AT connector, compatible with Deutsch DT, for robust motorsport wiring and a conformal-coated PCB to protect against moisture and harsh environmental conditions. It is important to note that the AXM-100 is not compatible with current-triggered tachometers, which are typically connected to the positive terminal of the ignition coil. For installation, the adapter should be wired inline between the ECU's tach output and the original tachometer input. Secure mounting with adequate strain relief on the wiring is recommended.