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Spark Plug: Description and Operation



V8 DFI Engines

Cayenne S Spark Plugs







The V8 naturally aspirated engine has nickel-yttrium spark plugs with four ground electrodes.

The four ground electrodes are arranged around the ceramic insulator in these surface gap spark plugs. The sparks -1- cross the surface of the insulator -4- and arc across a small gas gap to the ground electrode -2-, which improves the ignition properties. The main advantage of the surface gap spark plugs is the self cleaning effect of the insulator foot tip, since any shunts that occur between the center electrode and the ground electrode through the surface gaps, in particular during a cold start, are eliminated.