MSD 8572 Corvette V8 Tach DriveDistributor w_Vacuum Advance Installation - Manual (Page 4)

 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
Figure 6 Changing the Advance Stop Bushing.
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.
lockIng ouT The cenTrIfugal
advance
1. Remove the advance components including
the springs, weights and the advance stop
bushing from the advance assembly.
2. Remove the roll-pin from the drive gear and
remove the gear from the shaft.
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.
6. Install the drive gear and roll-pin.
Note: If you want to lock out the vacuum advance
of the PN 8572 Distributor, see page 6.
Figure 6 Locking Out the Centrifugal Advance.
Figure 7 Locking Out the Advance.
Figure 5 Advance Stop Bushing Chart.
BUSHING SIZE APPROXIMATE
CRANKSHAFT
DEGREES
Red-Smallest 28
Silver 25
Blue 21
Black-Largest 18