Summit Racing SUM-830450-1 Installation Instructions

Summit Racing RPM Switch with Digital Readout
* Always disconnect the battery before attempting any electrical work on your vehicle.*
Caution: Do NOT allow any of the switch wires other than the RED (power
source) wire to touch any 12V source, as this will cause the hardware to
malfunction, destroying the functionality of the switch.

WIRING INSTRUCTIONS

Note: Automotive circuit connectors are the preferred method of connecting wires. However,
you may solder if you prefer.
Note: If doing an LS engine swap, pick up the tach signal wire from the ECM/ECU and then set the
tach switch to 4-cylinders.

MOUNTING INSTRUCTIONS

Power - Red Connect to a switched +12V source.
Ground - Black Connect to an engine block ground.
Tach Input – Grey Connect to the negative terminal of your coil, or, if using a high energy CD
ignition, connect to the tach output of the ignition system instead.
Ground Output - Blue Connect to the negative/ground side of the device that you want to activate
at the desired RPM.
Note: If the device to which the blue wire is attached draws more than 3 amps, a relay must
be used to drive that device or damage will occur to the unit.
If your vehicle has a separate ignition coil, connect the gray wire to the negative (-) side of the
coil – the wire that goes to the points or electronic ignition module.
If your vehicle has a GM HEI ignition, connect to the terminal marked 'TACH', or, on some
systems, a single white wire with a spade terminal.
If your vehicle has an after-market ignition – some systems will connect to the TACH output
terminal.
If your vehicle has a computer controlled ignition system, consult the service manual for the
wire color and location.
1 - SUM-830450-1
Installation Instructions for SUM-830450-1
Summit Racing Equipment
(rev. 08/2018)
www.summitracing.com