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EZF Ignition System

The EZF ignition system is a performance graph controlled ignition system. Ignition performance data is stored permanently in its memory. This ignition performance data is set up in such a manner that the optimal ignition timing is available instantaneously for each engine operating condition. A micro-computer in the ignition control unit processes all engine data.

If the permanently given performance data would be divided into small sections each point of intersection made up by engine speed and load would represent a memory point or one of the many ignition timing angles. There are 256 memory points, which store the ignition timing angles determined during testing.

In order to be able to actually call off ignition timing angles, which are somewhere between the permanently given angles, the computer uses interpolation to instantaneously calculate these intermediate values from the neighboring memory points. In this manner it is possible to have more than 4000 ignition timing values from the 256 permanently stored values.

A special advantage of this ignition system is that in full throttle range the ignition timing can be selected for maximum torque. In partial throttle range the ignition timing is selected for minimum fuel consumption while conforming with emission control standards.

Fig 1: EZF Ignition System (928S)
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