MSD Pro-Billet Front Drive Distributor Chevrolet Small Block, PN 8510 - Big Block, PN 8520

ASSEMBLY Prior to installation, it is recommended to position the engine at your desired timing.
1. Install the distributor assembly using the four supplied socket head cap screws and washers.
2. Install the camshaft pulley with the supplied cam adapter, washer and 12-point bolt. Note that the threads are reversed. Coat the threads of the bolt with 30-weight motor oil or ARP moly lube. Torque it to 90 lb-ft with motor oil or 70 lb-ft with the ARP lube. Loop the belt over the timing belt pulley.
3. With number one cylinder at the desired timing, position the rotor so it is aligned with the terminal that will be number one in the firing order. This is recommended to get the rotor phasing close enough to run the engine. Rotor phasing should be checked and adjusted with the engine running.
4. With the rotor tip aligned, adjust the tension of the distributor drive belt. This is adjusted with the three bolts on the back of the housing (Figure 3). Squeeze the belt in the middle until there is about one inch between the belt with light pressure.
Rotor Phasing
Rotor phasing can be adjusted by loosening the band clamp and rotating the head assembly. It is recommended to modify a distributor cap by drilling a hole near the terminal so you can see exactly where the rotor tip is in relation to the cap terminal when the ignition fires. See the supplied Tech Bulletin concerning Rotor Phasing for more details.

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