FAQ's

Spark Plugs

What is the heat rating of a spark plug?

A spark plug must dissipate the heat produced by the combustion gasses. The heat rating is a measure of the amount of heat dissipation. A hot type spark plug’s firing end heats up quickly as there is a greater surface area exposed to the hot combustion gasses and heat transfer to the engine head is slower.  On the other hand, a cold type spark plug’s firing end does not heat up quickly as it has less surface area exposed to the hot combustion gasses and heat transfer to the engine head is quicker.