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HarryD HarryD is online now
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Join Date: May 2002
Location: Portland, Oregon
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Quote:
Originally Posted by mysocal911 View Post
Really? Why has Porsche since the 911 3.2, and all OEM ICE automotive manufacturers, use inductive discharge ignitions, i.e. NO CDIs?

That's the argument used in the '50s & '60s!
Several reasons. The Kettering Ignition has, in relative terms a short, weak spark. CDI produces a short, strong spark. An Inductive spark produces a long, strong spark.

The reason for the ignition design evolution is to ensure the charge in the cylinder is fully burned at the correct time. At low RPM, Kettering is fine. CDI solved the problem of getting a strong spark at high RPM but did not help on the emissions front. Inductive ignition allows for a strong spark to ensure emission compliance.

Different courses for different horses.
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Old 09-15-2024, 08:31 AM
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