Installation Owner's manual

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M S D I G N I T I O N • w w w. m sd ig ni ti on .c om • ( 91 5) 8 5 7- 52 00 • F A X (9 15 ) 85 7- 33 4 4

MSD Pro-Billet Ready-to-Run

Chevrolet V8 Distributor Kit

PN 8474

Important: Read these instructions before attempting the installation.

Parts Includ ed:

1 - Pro-Billet Distributor

1 - Rotor, PN 8467

1 - Distributor Cap, PN 8433

1 - Wire Retainer

2 - 1.5" Self Tapping Screws

2 - 10-32 x 3/4" Socket Head Screws

1 - Advance Kit

Note: The terminals of this Distributor Cap 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 gear is ever replaced, MSD Gear (PN 8531) is required for replacement due to the .500"

diameter shaft.

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. (When checking Total timing, disconnect

the vacuum canister and plug the vacuum source.)

Vacuum Advance: The vacuum advance will advance the timing up to 10° during partial throttle

driving (with 15 lbs of vacuum). The vacuum line should be routed to a ported vacuum outlet above

the throttle plates.

Note: MSD Distributors are supplied with the heavy (slow) advance springs 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.

1 - 3-Pin Harness

1 - Gasket

1 - Tube of Gear Lubricant

2 - O-Rings

1 - Vacuum Advance Lockout Kit

1 - Coil Wire

1 - Blaster SS Coil, PN 8207

WARNING: Before installing the MSD Ready to Run Distributor, disconnect the battery cables.

When disconnecting the battery cables, always remove the Negative (-) cable ﬁrst

and install it last.

Summary of content (8 pages)

PAGE 1
MSD Pro-Billet Ready-to-Run Chevrolet V8 Distributor Kit PN 8474 Important: Read these instructions before attempting the installation. Parts Included: 1 - Pro-Billet Distributor 1 - Rotor, PN 8467 1 - Distributor Cap, PN 8433 1 - Wire Retainer 2 - 1.
PAGE 2
INSTALLATION INSTRUCTIONS 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.
PAGE 3
INSTALLATION INSTRUCTIONS CENTRIFUGAL ADVANCE CURVE Selecting the Advance Springs Timing Curve From Factory 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.
PAGE 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.
PAGE 5
INSTALLATION INSTRUCTIONS 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.
PAGE 6
INSTALLATION INSTRUCTIONS Red to coil positive + Orange To Coil negative - Black To engine ground IGNITION KEY ORANGE TO 12V RED + ORANGE RED BLACK BLASTER SS COIL PN 8207 BLACK TO GROUND Figure 10 Wiring the Ready-to-Run Chevrolet Distributor. Note: The Ready-to-Run Distributors do not require an MSD Ignition, though they can be used with one.
PAGE 7
INSTALLATION INSTRUCTIONS VACUUM ADVANCE LOCKOUT If you do not want to use the vacuum advance canister of the MSD Distributor, MSD has supplied the distributor with a lockout mechanism. The Lockout assembly replaces the vacuum canister and will hold the pickup assembly firmly in place. The installation is easiest with the distributor out of the engine. 1. Remove the two Allen head screws that hold the advance canister (Figure 12). 2.
PAGE 8
Installation Option: This Cap can also be bolted down to an MSD Pro-Billet or Billet Distributor base with the supplied hardware. To accomplish this, the spring clips must be cut off (Figure 14). Note: When the cap is bolted down, the location of the spark plug wires must be changed. Figure 14 Optional Installation by Bolting the Cap Down. Service In case of malfunction, this MSD component will be repaired free of charge according to the terms of the warranty.