C3 Corvette Ignition - Distribution Of Power

Disconnect the distributor's three-wire connector.

Next, remove the vacuum line from the vacuum-advance canister on the distributor. You should also remove the bolt and distributor hold-down bracket.

Since '72s have mechanically driven tachometers, you must also remove the drive from the distributor.

With all of this accomplished, you can remove the distributor. Notice the cast-aluminum construction of the housing on this unit.

MSD's distributor housing is CNC-machined from an aluminum billet and uses high-quality sealed ball bearings. The two rotary dials shown here control the centrifugal and vacuum advance timing curves. A third dial (not shown) controls the rev limiter.

This port for the vacuum-advance signal is located on the bottom, where it won't interfere with wiring.

MSD engineers have spent untold hours testing and evaluating the metallurgy of their distributor gears. The result is a perfect combination of metallurgical composition, heat-treating, and coatings to provide the most durable and accurate gear possible.

MSD's rotors are injection-molded from Rynite material for superior strength and dielectric properties. They also use deep, molded vanes to agitate the air inside the cap, preventing ionization. The stainless steel/brass tip is screwed in place, and the screws are set deep in the housing to prevent spark scatter.

Since we planned to leave the tissue dispenser on the shelf, we took this opportunity to remove its mounting brackets as well. Remember to torque the intake manifold bolts back to spec.

MSD supplies a new distributor gasket, so you'll want to remove all traces of the old one. Plug the hole with a rag to prevent gasket shrapnel from falling into the engine.

Now the fresh gasket can be put in place.

A packet of Comp Assembly Lube is also included with each distributor. Apply this liberally to the distributor gear before installation.

You can now set the distributor in place. Make sure the rotor is facing the same direction as the old one.

If it's not, use a screwdriver to turn the oil pump to achieve alignment. This may take a few tries to get right. You can then loosely bolt the hold-down bracket back in place.

Next, disconnect the wiring and remove the stock coil.