MSD 8572 Corvette V8 Tach DriveDistributor w_Vacuum Advance Installation - Manual (Page 6)

INSTALLATION INSTRUCTIONS
M S D I G N I T I O N
• w w w . m s d i g n i t i o n . c o m • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • FA X ( 9 1 5 ) 8 5 7 - 3 3 4 4
VACUUM ADVANCE LOCKOUT
If you do not want to use the vacuum advance
canister of the PN 8572, MSD has supplied a
lockout mechanism.
1. Remove the two Allen head screws that hold
the advance canister (Figure 11).
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 12). 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 12 Checking Installation of the Lockout Plate.
Figure 11 Removing the Vacuum Canister.
ReluctoR
Paddles
canisteR
scRews
Mag PickuP
Plate
snaP
Ring
MECHANICAL DRIVE
When using a stock GM mechanical drive tach the supplied square tach drive adapter must
be used. The gear drive comes pre-lubed from the factory. When lubricating the tach cable,
it is recommended to lube the gear set. The backlash is set at the factory, however it can be
adjusted.