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This system helps to provide protection from "Spark Knock" on 8-cylinder engines. The system employs a detonation sensor mounted in the number two branch of the intake manifold. The sensor is tuned to the frequency that is characteristic of engine knocking.

When the knock frequencies are detected, the detonation sensor sends a low voltage signal to the Electronic Spark Control computer. The computer will then retard the timing a maximum of 20 degrees. The amount of decrease in timing is directly proportional to the strength and frequency of the detonation condition. When the condition is removed, the timing is advanced to the original value and the detonation suppression system will no longer influence ignition timing.