INSTALLATION INSTRUCTIONS

7

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.