MSD 6al box Tach Problems
- Thread starter punkn50
- Start date
cenok is family
15 Year Member
Cobra912
Active Member
which tach? If it's your factory tach you will have to splice into factory wiring to go to the box. If it's an external mount tach like an autometer etc. then you will have to run the wire staright from box to tach. Do as cenok is family suggested. Run a single wire from the tach output on the side of the box and connect it with a spade connector. MSD calls it a Faston connector. This output provides a vaiable signal I believe.
Make sure that you check out which tach you have and that it does not require a tach adaptor made by MSD to work. You'll find this in their on-line instructions.
http://www.msdignition.com/pdf/6%20series/6series.pdf
TACHOMETERS
The MSD Ignition features a Tach Output Terminal on the
side of the unit. This terminal provides a trigger signal for
tachometers, a shift light or other add-on rpm activated
devices. The Tach Output Terminal produces a 12 volt square
wave signal with a 20% duty cycle.
Some vehicles with factory tachometers may require a Tach
Adapter to operate with the MSD. For more information on
Tachometers and MSD Tach Adapters, see the Tachometer
Section on page 7.
If your GM vehicle has an inline filter it may cause the tach to
drop to zero on acceleration. If this occurs, bypass the filter.
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.
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 tach
output terminal on the side 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.
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 8910 8920
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 Tach Output Terminal on the MSD 6 Series Ignition Unit using the supplied Female Faston Receptacle.
Make sure that you check out which tach you have and that it does not require a tach adaptor made by MSD to work. You'll find this in their on-line instructions.
http://www.msdignition.com/pdf/6%20series/6series.pdf
TACHOMETERS
The MSD Ignition features a Tach Output Terminal on the
side of the unit. This terminal provides a trigger signal for
tachometers, a shift light or other add-on rpm activated
devices. The Tach Output Terminal produces a 12 volt square
wave signal with a 20% duty cycle.
Some vehicles with factory tachometers may require a Tach
Adapter to operate with the MSD. For more information on
Tachometers and MSD Tach Adapters, see the Tachometer
Section on page 7.
If your GM vehicle has an inline filter it may cause the tach to
drop to zero on acceleration. If this occurs, bypass the filter.
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.
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 tach
output terminal on the side 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.
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 8910 8920
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 Tach Output Terminal on the MSD 6 Series Ignition Unit using the supplied Female Faston Receptacle.
Cobra912
Active Member
Similar threads
