Msd 8381 GM LT-1 5.7L 93-94 Distributor Installation- User Manual

IMPORTANT: Due to the number of applications and years that the LT-1 Distributor is used on, it is highly

recommended to have the Service Manual for your vehicle during this installation.

IMPORTANT NOTES BEFORE INSTALLATION

Throughout its

course, the GM

LT-1engine used

two

different

drive

mecha-

nisms to con-

nect the cam to

the

distributor.

Figure 1 shows

the drive for the

MSD PN 8381

Distributor. This

design is used in

the early model distributors. Make sure this is correct for your application.
Before removing the distributor it is recommended to mark the location of the rotor. This is to ensure

that the distributor and cam are indexed correctly prior to reassembly.
Be sure that the O-ring between the distributor cap and the housing is in place before installing the

cap. The O-ring must be stretched out, then installed onto the housing. It will shrink back to size.

TIMING INFORMATION

Since the timing of the MSD Pro-Billet Distributor can be adjusted, it is recommended that a timing indicator

and mark be fabricated prior to installing the distributor. This way, the timing can be recorded so the MSD

Distributor can be set to the same amount. From the factory,

the MSD Distributor is set to the OEM specs (one and a half

turns).
The MSD Distributor can alter the timing +/-6°, with a quar-

ter turn equalling 1° of timing. The adjusting screw has a soft

Loctite compound applied to it for a seal (Figure 2). Repeated

adjustments may loosen the screw. If this occurs, remove the

screw and apply Blue Loctite

®

to the threads. The screw can

safely be removed from the distributor.
Too much advance may cause detonation resulting in the

ECU retarding the timing through the engine’s knock sensor.
When adjusting the timing, take note that the ECU varies

the timing at an idle. It is recommended to bring the engine

rpm up to 1,500 - 2,000 when setting the timing.

MSD Pro-Billet LT-1 Distributor

'93-'94 F-Body, '92-'94 Corvette, '92-'94 Full Size

PN 8381

Parts Included:

1 - Distributor

1 - Cap

1 - Rotor

1 - Isolator

2 - Rotor Screws

1 - O-ring

3 - 1/4-20 x 2" Socket Head Cap Screws

5 - 8-32 x 0.5" Phillips Screws

1 - Vacuum Line Assembly

1 - Removal Tool

Figure 2 Adjusting the Timing.

Figure 1 The Drive Mechanism of the PN 8381 Distributor.

TIMING

ADJUSTER

CAMSHAFT

STOCK DISTRIBUTOR

INDEX

FLAT

SPOT

INDEX

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

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