AC K10 spark plug --- modern equivalent

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On ‎8‎/‎18‎/‎2017 at 10:29 PM, scott12180 said:

Could someone  post the article or post the details of this test  which resulted in more than 75% failure on AC spark plugs? 

I'm not a club member as I don't own a Cadillac-LaSalle, but I am very interested in how the test was done and which spark plugs were effected.  I think we all could benefit from these results.



Having made millions of them while going to school,  I would like to see the testing and failure mode.  Also would like to know what the definition of "failure" is.  Does not sound even closely real.  Maybe 1 in several thousand plugs, but not 75% failure rate.  Baloney.

Edited by Larry Schramm (see edit history)
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Pebble has come and gone. We had a good time and a great car on the field. Here are some photos of the car on the field. Included is a shot of the engine with the plugs installed. The car started and ran fine. All the plugs were good. Ed








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I have some NOS AC K-12 if you need them

On 8/14/2017 at 10:11 PM, scott12180 said:

Packard service literature in the early 1930's recommends AC spark plugs---  type K9, K10 or K12 for my 1932, depending on the heat range.


I've yet to find a list of what the modern designation for these plugs would be. 

These are 14 mm plugs but what's important is the heat range ---   K9 is cooler, K12 is hotter --- and especially the reach into the cylinder.   

I'd like some NOS plugs.  Nothing much on eBay. . . .


Any suggestions?



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