Thread: muscle car data
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Old 10-11-2003, 11:50 AM
Duke2.6 Duke2.6 is offline
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Join Date: Mar 2003
Location: Southern California
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Modern emission controlled cars have very powerful ignition systems. They have to in order to reduce misfires to a minimum to pass emission certification tests.

Many aftermarket vendors advertise large voltages, but these are meaningless. The actual voltage required for a spark to bridge the plug gap is rarely more the 10-12 kilovolts.

The real measure of ignition system performance is per spark energy and spark duration. Energy is usually measured in "millijoules", but it's rarely specified.

CD ignitions are popular, but they are poor choices and never used by OEMs. Street engines need long duration sparks to ignite low density, lean, and exhaust gas diluted mixtures. Inductive systems provide the long duration necessary.

One well known CD ignition manufacturer hypes their multiple sparks at low engine speeds. Well, multiple sparks are necessary to avoid excessive misfiring, but the second and third sparks arrive considerably after the proper timing point.

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