INSTALLATION INSTRUCTIONS 7
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• W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 8 5 7 - 3 3 4 4
NO-RUN ON FOREIGN VEHICLES
Some foreign vehicles with fuel injection systems may require an MSD Tach/Fuel Injection Adapter
to run with an MSD 6 Series Ignition. This is because many of these systems use the same trigger
source to operate the MSD, the tachometer and the fuel injection. This results in a voltage signal
that is too low to accurately trigger the fuel injection. To fix this, an MSD Tach Adapter, PN 8910,
will remedy the problem on the majority of vehicles. If the PN 8910 does not fix the problem, the PN
8910-EIS will be required.
Note:
Toyotas and Ford Probes will require the PN 8910-EIS Adapter.
INOPERATIVE TACHOMETERS
If your tachometer fails to operate with the MSD installed you may need an MSD Tach Adapter. Before
getting an Adapter, try connecting your tachometer trigger wire to the Gray tach wire of the MSD.
This output produces a 12 volt, square wave (see page 2). If the tach still does not operate, you will
need a Tach Adapter. There are two Tach Adapters:
PN 8920:
If you are using the Magnetic Pickup connector (Green and Violet wires) to trigger the MSD,
you will need the PN 8920.
PN 8910:
If your tachometer was triggered from the coil
negative terminal (voltage trigger) and you are using the
White wire to trigger the MSD you will need the PN 8910.
BALLAST RESISTOR
If you have a current trigger tach (originally coil positive)
and use the White wire of the MSD, you can purchase a
Chrysler Dual Ballast Resistor (used from 1973 - 1976)
and wire it as shown in Figure 5.
Tachometer Compatibility List
AFTERMARKET TACHOMETER WHITE WIRE TRIGGER
MAGNETIC TRIGGER CONNECTOR
AUTOGAGE 8910 8920
AUTOMETER
NONE
NONE
FORD MOTORSPORTS
NONE
NONE
MALLORY
NONE
NONE
MOROSO
NONE
NONE
STEWART (voltage triggered)
8910
8920
S.W. & BI TORX
NONE
NONE
SUN
8910
8920
VDO
NONE
NONE
AMC (JEEP)
8910
8920
CHRYSLER
8910
8920
FORD (voltage triggered)
8910
8920
GENERAL MOTORS
Bypass In-Line Filter
Bypass In-line filter
IMPORTS
8910
8920
Note:
On the list above, the trigger wire on tachometers that are marked NONE may be connected to the Gray
Tach Output Wire on the MSD 6AL Ignition.
Figure 5 Wiring the Dual Ballast Resistor.
Figure 4 Common Tachometers and Adapters.
LED
The LED will flash for every trigger signal from the distributor or crank trigger. You can take advantage
of this when statically setting the timing when false triggering the box to troubleshoot. Also, when
the engine is not running, the LED will be On when the key is in the On position.
TACH/FUEL ADAPTERS
If your tachometer does not operate correctly or if you experience a no-run situation with your foreign
vehicle you probably need an MSD Tach Adapter. The chart in Figure 4 lists common tachometers
and if an Adapter is necessary.
