Spark Plug Characteristics
Inside the spark plug is a central inner electrode that is insulated from heat by its white porcelain shell. It gets electricity to perform a spark via the central electrode which is connected to your vehicle’s ignition coil by a heavily insulated wire.
The bottom part of the plug is threaded to allow it to be screwed into your engine’s cylinder head. The bottom tip extends further into the combustion chamber where ignition of the air/fuel mixture takes place.
Heat Range Explained
Besides acting as a source of ignition, the other important role a spark plug plays is to transfer heat from the combustion chamber into the cooling system. This ability to dissipate heat is defined by the spark plug’s heat range. The heat range must be matched to your application or pre-ignition and fouling (electrical leakage that causes a misfire) of the spark plug can occur.
You may hear spark plugs being referred to as ‘cold’ or ‘hot’. This is referring to your spark plugs heat range. Changing to a hotter or colder spark plug should be done with extreme caution as running a spark plug that is too hot for your needs can damage your engine.
