TACHOMETER SENSE LINE ATTACHMENTS AND METER SCALING
GASOLINE ENGINES
The WHITE/DIMMER circuit must be installed and supply 3 to 12vdc before the PPR can be
progammed
Attach the sensing line to the primary side of a spark coil, and then set the calibration PPR value for
your spark configuration, using directions for the CALIBRATION option.
Once upon a time, there was just one configuration: a spark coil, a distributor, and then wires from the
distributor cap to the individual sparkplugs. If your car is like this, use the table below:
FOR “CLASSIC” ONE-IGNITION-COIL ENGINES
IF YOU HAVE ONE
COIL PER PLUG CONNECT TO ANY SPARK COIL PRIMARY
IF YOU HAVE ONE COIL PER TWO PLUGS CONNECT TO ANY SPARK COIL PRIMARY
DIESEL ENGINES
Modern diesel engines usually have camshaft sensors or electronic injector pumps. If there is one
injector per cylinder, the signal from the pump drive will be 1/2 PPR. Similarly, if there is a camshaft
sensor signal the signal will be ½ PPR. Set the calibration at a reading of 500.
If there is no electronic cam sensing or fuel injection in your diesel engine, the procedure is more com-
plex. A signal can be obtained from the alternator by attaching a wire directly to the winding of the sta-
tor before it goes to one of the rectifier diodes. This signal will be proportional to engine speed, but the
Programming Instructions for : RPM Tachometer
2
1/16
” Controller
8
# PLUG
2
4
6
8
10
12
PULSES PER
REVOLUTION (PPR)
1
2
3
4
5
6
METER
SETTING
1000
2000
3000
4000
5000
6000
# PLUG
Any
PULSES PER
REVOLUTION (PPR)
1/2
METER
SETTING
500
# PLUG
Any
PULSES PER
REVOLUTION (PPR)
1
METER
SETTING
1000