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Spark Plugs, A Pictorial Description

new 5/06/2004

Who carries Denso plugs? How much do they cost?
Dwayne Clites


First picture shows the difference between the Denso IT16 and the Motorcraft AGSF32FM (this is the AWSF32FM replacement.) Note the thinner iridium electrode and the U shaped channel on the ground electrode, the plug seats are in the same place.

Second picture shows the AWSF32FM and the AGSF32FM side by side.

Third is a AWSF32FM that was in the car for about 30k, this plug was installed by Kirk last year when the cams were welded. What is significant about this shot is that the center electrode has eroded away, the gap is at .055. This plug was in cylinder #7, the coil for this cylinder was showing some cracking in the plastic.



Autozone has them, I'm sure others do as well. Stock size/temp is the IT16 Part.
Cost is like 12.99 each (maybe it is 11.99).
Scott Krietemeyer
99 TG
96 MG


Have seen them at my local AutoZone recently.

Not sure if I have explained the theory behind the thinner center electrode idea, for those who understand it I apologize but have had an inquiry recently: It has to do with reducing electrical resistance at the center electrode of the plug. Some of the best conductors also have very low melting points and therefore require a lot of material to prevent melting in the combustion chamber, however increasing material increases electrical resistance therefore defeating the advantage of the good conducting material. The iridium material has higher melting point with very good electron transfer properties. This transfers more electrons meaning a more energized hotter spark

Carter Fuji

'97 ES Whoosh


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