by Todd Ryden
(Taken from High-Performance Ignition Systems by Todd Ryden)
Have you ever stopped to wonder how all of the trigger signals, timing, and delivery of spark would occur if there were no distributor at all? That’s right, no distributor. Actually, new cars don’t use distributors anymore. However, most hot rods and traditional domestic performance engines use a distributor (although the late-model Hemi, Coyote, and LS engines are challenging that).
As electronic engine management system development progressed, the roles of the distributor continued to diminish until they completely disappeared. The majority of racing and performance cars still use distributors, which is why I include them throughout this discussion. However, the distributorless contingent is growing. Both systems still need a trigger source and electronics to control the charging and operation of the coils, whether it’s through the distributor or through an electronic control unit (ECU) and electronic ignition module.
Several variations of the distributorless ignition systems (DIS) are available. Coil pack models have a coil with two towers and fire two cylinders. These have a variety of ignition upgrades available. Other versions have a coil for every cylinder. The latest systems even have the coil mounted right to the spark plug with no spark plug wire. Some companies even specialize in an entire system that allows you to obsolete your own distributor.
Whatever type of ignition system your engine sports, they all have shared traits, including what it takes to upgrade their performance.
Even if your engine doesn’t have a distributor, the theory of a distributor-triggered ignition system remains. Instead of a trigger from the distributor going to the coil, a signal from a crankshaft sensor is responsible for triggering the coil’s high voltage.