MSD Pro Mag 12 LT Chrysler PN 7910 Installation

1. Install the set screw into the intake manifold or engine block.
2. Install the magneto into the engine. On Chevrolet engines, position it so the hold down clamp will align with the housing’s anti-rotation collar.
3. Install the billet clamp over the set screw and on to the collar of the magneto. Put the flat washer, lock washer and the nut onto the stud and tighten the assembly.
Note: On Chevrolet applications, it is recommended to locate the wiring harness of the generator towards the left side injector stack (Figure 1). This also puts the timing indicator of the magneto in a position that should be easy to view. Also position the band clamp’s retaining screw so it points to the left and is in the back of the magneto, close to the firewall. On Ford and Chrysler engines, rotate the base until the pointer is easy to view.
4. Locate which cap terminal is going to be the number one cylinder. Mark on the housing this location then remove the cap.
5. Loosen the band clamp and position the generator so the rotor tip is just leading into the number one cylinder mark (from step 6) indicating the number one cylinder (Figure 3). This will put the timing approximately 2°-3° within TDC or where you have the timing set. Note: Always verify timing with a timing light. Chevy/Chrysler - Clockwise Rotation Ford -Counterclockwise Rotation
6. Install the cap and spark plug wires. Recommendation: It is recommended on Chevrolet applications to put the number one cylinder in the position shown in Figure 4. The custom wire sets MSD offers are designed for this setup.

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