ONLINE PRODUCT REGISTRATION: Register your MSD product online and you’ll be entered
in our monthly 8.5mm Super Conductor Spark Plug Wire give-away! Registering your product
will help if there is ever a warranty issue with your product and helps the MSD R&D team create
new products that you ask for! Go to www.msdperformance.com/registration.
Important: Read these instructions before attempting the installation.
WARNING: Before installing the MSD Distributor, disconnect the battery cables. When disconnecting
the battery cables, always remove the Negative (-) cable first and install it last.
Note: The terminals of this Distributor require spark plug style terminals. You may need to change the
terminals and boots of your wires. MSD offers two kits, PN 8849 or PN 8848 that are supplied with
nine boots and terminals.
Note: If the Chevy gear is ever replaced, MSD Gear, PN 8561, is required for replacement due to the
.500" diameter shaft.
2 - 1.5" Self Tapping Screws
2 - 10-32 x 3/4" Socket Head Screws
1 - Advance Kit
1 - Gasket/O-Ring Seal
1 - Tube of Gear Lubricant
2 - O-Rings (Chevy Only)
1 - Green Tach Jumper
TIMING FUNCTIONS
Before continuing with the installation, here are a few definitions you should be aware of:
Initial Timing: This is the base timing (also referred to as idle timing) of the engine before the centrifugal
advance begins.
Centrifugal Advance: The centrifugal (or mechanical) advance mechanism is made up of weights, springs,
advance cams, and an advance stop bushing. The amount and rate of advance that your distributor is
capable of is determined by the centrifugal timing. If you ever wish to lock out the centrifugal advance,
refer to the centrifugal advance section.
Total Timing: This is the total of the initial timing plus the centrifugal advance added together. Example:
10° Initial + 25° Centrifugal = 35° Total Timing.
Note: MSD Distributors are supplied with the heavy (slow) advance springs and the 21° stop bushing
installed. This is to prevent detonation in certain applications. Review the information on pages 2-4
to determine the best advance curve for your application.
M S D • 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
Page 2
2 INSTALLATION INSTRUCTIONS
RPM LIMIT AND TACHOMETER INFORMATION
Tach Signal: The Ready-to-Run Distributor features a Green Tach Output wire which provides a clean
signal for most tachometers and even some aftermarket fuel injection systems. The signal
output is a 12 volt square wave, 20° duty cycle. This wire is also responsible for programming
the built-in rev limiter.
Rev Limiter: The Ready-to-Run Distributor has a built-in rev limit that can easily be adjusted from 2,000 rpm
to over 10,000 rpm. The default is 10,000 rpm. To set the rev limiter, run the engine to half the
desired rpm then ground the Green Tach wire (a jumper is supplied) for approximately one
second. Every time the key is turned to the On position, the tach will display the programmed
rpm limit. See page 8 for the programming procedure.
CHOOSING AN ADVANCE CURVE
The function of the advance curve is to match the ignition timing to the burning rate of the fuel and speed
(rpm) of the engine. Any factor that changes the burning rate of the fuel or the engine speed can cause
a need for an ignition timing change. Figure 1 shows some of the factors that will affect engine timing.
FACTOR Advance Timing Retard Timing
For For
Cylinder Pressure Low High
Vacuum High Low
Energy of Ignition Low High
Fuel Octane High Low
Mixture (Air/Fuel) Rich Lean
Temperature Cool Hot
Combustion Chamber Shape Open Compact
Spark Plug Location Offset Center
Combustion Turbulence Low High
Load Light Heavy
Figure 1 Ignition Timing Factors.
As you can see from the chart, most factors will change throughout the range of the engine operation.
The timing mechanism of the distributor must make timing changes based on these factors.
Example: An engine has 11:1 compression, a high energy ignition and turns 5,500 rpm. With the
specifications given, you will have to retard the timing for the high compression and high energy ignition.
By comparing the engine’s specifications against the chart, a usable timing guideline can be found.
Engines with a combination of items from both columns will require a timing that is set in the mid range.
Obviously a full technical explanation of correct ignition timing would be very complicated. The best way
to arrive at a suitable ignition curve for your engine is to use the Ignition Timing Factors Chart as a guide
and compare it to the Advance Graphs in Figure 4 until a suitable curve is found. When selecting your
advance curve, use detonation (engine ping) as an indicator of too much advance, and a decrease in
power as an indicator of too little advance.
TIPS ON SELECTING AN ADVANCE CURVE
• Use as much initial advance as possible without encountering excessive starter load.
• Start the centrifugal advance just above the idle rpm.
• The starting point of the centrifugal advance curve is controlled by the installed length and
tension of the spring.
• How quickly the centrifugal advance (slope) comes in is controlled by the spring stiffness. The stiffer
the spring, the slower the advance curve.
• The amount of advance is controlled by the advance bushing. The bigger the bushing, the
smaller the amount of advance.
M S D • 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
Page 3
INSTALLATION INSTRUCTIONS 3
30°
20°
10°
40°
0
1000 2000 3000 4000 5000
6000
RPM
A
ADVANCE
STOP
BUSHING
D
E
G
R
E
E
S
BLUE
2-SILVER (HEAVY) SPRINGS
CENTRIFUGAL ADVANCE CURVE
SELECTING THE ADVANCE SPRINGS
The rate, or how quick the advance comes in
is determined by the type of springs which are
installed on the distributor. The MSD distributors
are equipped with two Heavy Silver springs
installed. These will give you the slowest advance
curve possible (Figure 2). The parts kit contains
two additional sets of springs which can be used
to match the advance curve to your particular
application. Refer to the Spring Combination Chart
(Figure 3) for combinations that can be achieved.
To change the springs, remove the cap and rotor
and use needlenose pliers to remove the springs.
Be sure the new springs seat in the groove on
the pin.
Timing Curve From Factory
Figure 2 The Factory Equipped Curve.
SPRING COMBINATION RATE OF ADVANCE FIGURE 4
2- Heavy Silver SLOWEST A
1- Heavy Silver B
1- Light Blue
1-Heavy Silver C
1-Light Silver
2- Light Blue D
1- Light Silver E
1- Light Blue
2- Light Silver FASTEST F
Figure 3 Spring Combination Chart.
Figure 4 Advance Curves.
M S D • 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
Page 4
4 INSTALLATION INSTRUCTIONS
SELECTING THE ADVANCE STOP
BUSHING
Three different advance stop bushings are supplied
in the distributor kit. The distributor comes with a
Blue (21°) bushing already installed. If a different
amount of centrifugal advance is desired, follow the
next procedure to change the bushings. The chart
in Figure 5 gives the size and approximate degrees
for the corresponding bushings.
CHANGING THE ADVANCE STOP
BUSHINGS
1. Remove the distributor cap and rotor.
2. Remove the locknut and washer on the bottom of
the advance assembly (Figure 6).
3. Remove the bushing and install the new one.
Install the washer and locknut. Use care not to
over-tighten.
BUSHING SIZE APPROXIMATE
CRANKSHAFT
DEGREES
Red-Smallest 28
Silver 25
Blue 21
Black-Largest 18
Figure 5 Advance Stop Bushing Chart.
Figure 6 Changing the Advance Stop Bushing.
LOCKING OUT THE CENTRIFUGAL
ADVANCE
1. Remove the advance components including the
springs, weights and the advance stop bushing
from the advance assembly.
2. For Chevy models, remove the roll-pin from the
drive gear and remove the gear from the shaft. For
Ford models, remove the roll pin from the shaft
retaining sleeve and slide the sleeve down.
3. Slide the shaft two inches out of the housing.
4. Rotate the shaft 180° and insert the advance stop
bushing pin into the small hole on the advance
plate (Figure 7).
5. Install the locknut and washer to the advance stop
bushing pin. This locks the advance in place. Do
not over-tighten the locknut.
6. Install the drive gear or retaining sleeve and roll-pin.
Figure 6 Locking Out the Centrifugal Advance.
Figure 7 Locking Out the Advance.
M S D • 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
Page 5
INSTALLATION INSTRUCTIONS 5
CHAMFER
EDGES
CHAMFER
EDGES
DISTRIBUTOR
HOUSING
O-RINGS
ROTOR
INSTALLING THE DISTRIBUTOR
1. Remove the existing distributor cap without
disconnecting any of the spark plug wires.
2. With the cap off, crank the engine until the
rotor is aimed at a fixed point on the engine or
firewall. Note this position by making a mark
(Figure 8).
3. Place the distributor cap back on and
note which plug wire the rotor is pointing
to. MARK THE SPARK PLUG WIRES and
remove the distributor cap.
4. Disconnect the wiring from the distributor.
5. Loosen the distributor hold down clamp
and slide the clamp out of the way.
6. Lift the distributor out of the engine. Note
that the rotor rotates as you lift the distributor
out. This is due to the helical cut gear and
should be taken into consideration when
installing the new distributor.
7. Install the gasket and apply a liberal amount
of the supplied lubricant to the distributor
gear. (The supplied O-rings can only
be used if the Chevrolet block has been
modified as shown in Figure 9.)
8. Install the distributor making sure that the
rotor comes to rest pointing at the fixed mark.
If the distributor will not fully seat with the rotor
pointing to the marked position, you may need
to rotate the oil pump shaft until the rotor lines
up and the distributor fully seats.
9. Position and tighten the hold down clamp onto
the distributor.
10. Install the distributor cap and spark plug wires
one at a time to ensure correct location. A
wire retainer is supplied to secure the wires
in place. Align the mounting bosses and use
the supplied 1.5" self-tapping Phillips screws
to hold the retainer in place (Figure 10).
11. Page 7 shows how to set the rev limiter and
connect the tachometer.
MARK
Figure 8 Marking the Rotor Location.
Figure 9 Modified Chevy Block for use with O-Rings.
CARB.
VALVE
COVER
M S D • 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
Figure 10 Installing the Wire Retainer.
Page 6
6 INSTALLATION INSTRUCTIONS
WARNING: High voltage is present on the coil terminals. Do not touch the terminals or
coil tower when the engine is cranking or running.
RED
ORANGE
BLACK
ORANGE
RED
ORANGE
BLACK
GREEN TO
TACH INPUT
IGNITION KEY
TO 12V
RED
BLACK
TO GROUND
Figure 11 Wiring the Marine Ready-to-Run Distributor.
TO COIL POSITIVE + 12 VOLTS
TO COIL NEGATIVE
-
TO ENGINE GROUND
+
HEAVY RED
HEAVY BLACK
NITIO
IG
Multiple
Spark
Discharge
MSD 6M-2 MARINE IGNITION
N
PN 6460
TO BATTERY +
TO GROUND
AUTOTRONIC CONTROLS CORPORATION
PART NO.
SERIAL NO..
GRAY
TO 12 VOLTS
TO PN 8768
REV CONTROL
TO TACH
RED
WHITE
TO KEY IGNITION
GREEN
NOT USED
+
VIOLET
RED
ORANGE
BLACK TO
GROUND
ORANGE
BLACK
BLACK
ORANGE
GREEN TO
TACH INPUT
+
COIL
RED
Figure 12 Connecting the Marine Ready-to-Run Distributor to a 6M-2 Ignition Control.
M S D • 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
Page 7
INSTALLATION INSTRUCTIONS 7
TACHOMETER INFORMATION
The MSD Ready-to-Run has a Green wire that provides a 12 volt square wave, 20° duty cycle tachometer
signal that will trigger most tachometers. It is recommended to connect this lead to your tach’s trigger
input wire and check its operation. Note that the rpm limiter is extremely accurate and due to the variety
of tachometers available, there may be differences in the displayed rpm.
PROGRAMMING THE REV LIMIT
A tachometer is required to set the rev limit. The limit is programmed by
running the engine at half the desired rpm, then momentarily grounding
the Green tach output wire from the MSD. A Green jumper wire is
supplied to connect to the tach with another tee-splice coming off to use
for programming. A switch may also be installed to ease adjustments of
the limiter (Figure 13). The default rpm limit is 10,000 rpm and the limit
is adjustable from 2,000 - over 10,000 rpm..
1. Start the engine and bring the rpm to half the desired rev limit (for a
6,000 rpm limit, raise and hold the rpm to 3,000).
2. While holding the rpm steady, short the Green tach wire to ground
for approximately one second. Note that the tach will go to zero
while grounded.
3. The tach will now display the programmed rev limit amount for two
seconds. If this value does not register on the tach, repeat the procedure and try a different ground
source.
4. To confirm the rev limit value, turn the ignition key to the On position (without cranking the engine). The
rev limit value will be displayed for two seconds on the tachometer.
OPTIONAL
PROGRAMMING
SWITCH
TO
TACH
JUMPERGREEN
Figure 13 Setting the Rev Limiter.
Note: This rpm confirmation only displays when the Green wire is being used to trigger the tachometer.
In case of malfunction, this MSD component will be repaired free of charge according to the terms of the warranty.
When returning MSD components for warranty service, Proof of Purchase must be supplied for verification. After
the warranty period has expired, repair service is based on a minimum and maximum fee.
All returns must have a Return Material Authorization (RMA) number issued to them before
being returned. To obtain an RMA number please contact MSD Customer Service at 1 (888) MSD-7859 or visit
our website at www.msdperformance.com/rma to automatically obtain a number and shipping information.
When returning the unit for repair, leave all wires at the length in which you have them installed. Be sure to include
a detailed account of any problems experienced, and what components and accessories are installed on the vehicle.
The repaired unit will be returned as soon as possible using Ground shipping methods (ground shipping is covered
by warranty). For more information, call MSD at (915) 855-7123. MSD technicians are available from 7:00 a.m. to
5:00 p.m. Monday - Friday (mountain time).
Limited Warranty
M
SD warrants this product to be free from defects in material and workmanship under its intended normal use*,
when properly installed and purchased from an authorized MSD dealer, for a period of one year from the date of
the original purchase. This warranty is void for any products purchased through auction websites. If found to be
defective as mentioned above, it will be repaired or replaced at the option of MSD. Any item that is covered under
this warranty will be returned free of charge using Ground shipping methods.
This shall constitute the sole remedy of the purchaser and the sole liability of MSD. To the extent permitted by
law, the foregoing is exclusive and in lieu of all other warranties or representation whether expressed or implied,
including any implied warranty of merchantability or fitness. In no event shall MSD or its suppliers be liable for special
or consequential damages.
*Intended normal use means that this item is being used as was originally intended and for the original application
as sold by MSD. Any modifications to this item or if it is used on an application other than what MSD markets the
product, the warranty will be void. It is the sole responsibility of the customer to determine that this item will work for
the application they are intending. MSD will accept no liability for custom applications.
M S D • 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