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Rising edge vs falling edge

Road Tuning

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Just curious as to what the exact difference is between each ignition set up? Really just for personal knowledge

The description is off the help file from Link ECU . Hope it answers your question .

Spark Edge sets the edge of the ignition signal that causes the coil to fire a spark. The following options are available:

ยท Falling - The coil charging will start when the ignition signal goes high and fire the spark when the signal goes back low (FALLS from high to low) . On an oscilloscope this signal would be normally low with a high pulse equal to the length of the current dwell time.

ยท Rising - The coil charging will start when the ignition signal goes low and fire the spark when the signal goes back high (RISES from low to high). On an oscilloscope this signal would be normally high with a low pulse equal to the length of the current dwell time.

Do not confuse the Spark Edge setting with the trigger falling/rising edge settings.

The rising/falling edge setting needs to be set to suit your particular ignition system. If you have this wrong then you will quickly destroy your coils. The majority of OE ignition systems tend to be falling edge, however there are some notable exceptions such as Honda for example.