SN74Z Push Button Interface Module For ECM Or VSS

Description

The SN74Z is necessary when using a Classic Instruments speedometer with an Electronic Control Module (ECM) or Vehicle Speed Sensor (VSS) signal. Installs in
line between the transmission pulse signal or ECM speed output and your electronic speedometer. Will work with most aftermarket electronic speedometers.
Converts all known pulse signals to 16,000 ppm or 8,000 ppm signals and includes an additional 8,000 ppm output signal for cruise control.

The SN74Z has the following features when used as a Speedometer interface.
Input Source Options
Three wire pulse signal generator input source
Built-in Vehicle Speed Sensor (VSS) input source
Most Tremec transmissions
Later model 700R4’s         
Typically a sine wave signal
Two wire pulse signal generator input source
Classic Instruments SN96 or SN95
Typically a sine wave signal
One wire ECM signals input source
Typically a 5 volt square wave
Output
The output can be selectable between either 8000 pulse per mile or 16000 pulse per mile
Outputs a 12V square wave, 50% duty cycle
8000 pulse per mile cruise control output
Additional Benefits
Three different calibration options
Instant: drive 30 MPH and press the calibration button
Real-Time: press and the hold the calibration button to match the speedometer reading to the actual vehicle speed
Marked Mile: Drive a measured mile to calibrate the speedometer
Input signal can range from 2000-200,000 pulses per mile
State of the art signal averaging software that ensures smooth pointer operation, even in fluctuating signal conditions.
Noise-reducing, filtered power output for powered speedometer signal generators
 
The SN74Z has the following features when used as a Tachometer interface.
Input Source Options
High Voltage Coil signal input source
.5-6 pulses per revolution (1-12 cylinder engine)
Typically the negative side of an ignition coil
5-12V Square Wave signal input source
.5-6 pulses per revolution (1-12 cylinder engine)
20%-50% duty cycle
Typically from an electronic ignition box or computer
Inductive Gear tooth sensor input source
Typically used in diesel applications where there is not an ignition system
The sensor can be mounted to the engine near the flywheel to sense the gear teeth as they rotate by
Can be used with 32-510 tooth flywheels, 32-510 pulses per revolution
Output
Signal output
12V square wave, 50% duty cycle
2, 3, or 4 pulses per revolution (4, 6, or 8 cylinder)
3 preset flywheel tooth settings
148 tooth – Chevy Duramax
152 tooth – 5.9L Cummins
155 tooth – 7.3L Ford Powerstroke