Autolite Spark Plugs - The topic of today's discussion is spark plug heat ranges. Heat Range is the term used to describe the rate of heat transfer from the firing tip of
Importance of Heat Range – NGK
Heat Range | Basic Knowledge | SPARK PLUG | Automotive Service Parts and Accessories | DENSO Global Website
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BoschSparkPlugs.net: How Do I Find a Colder or Hotter Plug?