Duraspark

The biggest change, apart from the control box redesign, was the large distributor cap to handle the increased spark energy.

They were coded by the color of the plastic wire strain relief, or "grommet" as it is most often called, in order to make them easy to identify.

In addition to the color-coding, the modules may have a keyway molded into the electrical connectors to prevent accidental use in the wrong vehicle.

The system consists of a magnetic reluctor and pickup in the distributor, with a separate fender mounted ignition module to trigger the coil.

All timing is controlled by the engine computer, which is capable of firing the spark plug at any point within a 50-degree range depending on calibration.