Owners manual

6 INSTALLATION INSTRUCTIONS
MSD • WWW.MSDPERFORMANCE.COM • [phone] • FAX [phone]
VACUUM ADVANCE LOCKOUT
If you do not want to use the vacuum advance
canister, MSD has supplied a lockout mechanism.
1. Remove the two Allen head screws that hold the
advance canister (Figure 12).
2. Remove the snap ring that holds the magnetic
pickup assembly in place.
3. Gently lift up on the mag pickup plate and slide
the vacuum canister out.
4. Install the Lockout Plate in place of the canister.
Install the two retaining screws.
5. Install the supplied screw and washer through the
Lockout and tighten.
6. It is important to make sure the pickup plate
is parallel with the housing of the distributor
(Figure 13). If it is cocked or slanted, the paddles
of the reluctor may contact the pickup. Check
the clearance by rotating the distributor shaft.
If necessary, use the supplied shims under the
Lockout hold-down to correctly position the
pickup plate.
Note: If no shims were required, use one beneath the
washer of the Lock-Out Hold Down Screw.
Note: Do not forget to plug the original vacuum
advance hose.
Figure 13 Checking Installation of the Lockout Plate.
Figure 12 Removing the Vacuum Canister.
RELUCTOR
PADDLES
CANISTER
SCREWS
MAG PICKUP
PLATE
SNAP
RING
VACUUM ADVANCE
Your distributor is equipped with an
optional vacuum advance canister.
Vacuum advance is generally used
to improve cruising economy and
driveability, depending on the application.
The chart in Figure 11 shows the
relationship between engine vacuum and
the amount of ignition timing advance.
To connect the vacuum advance, connect
a vacuum hose from the canister to a
ported vacuum source on the carburetor
or throttle body. Ported vaccum sources
are located above the throttle plates so
there will not be an excessive amount of
timing advance at idle and lower engine
speeds.
0
2
4
6
8
10
12
14
12345678910111213141516
Inches of Vacuum
Degrees of Advance
OE Non Adjustable Vac. Adv. 1808
Figure 11 Vacuum Advance and Timing Chart.