Spark Plug Selection

The calorific value of the spark plug can be determined based on the engine's compression ratio, speed and air-fuel ratio.
The calorific value of commercially available spark plugs ranges from 5 to 13. The larger the value, the "cooler" the spark plug is, which is the so-called cold type. High compression ratio engines require the use of cold type spark plugs. The smaller the value, the "hotter" the spark plug is, that is, the hot type. Low compression ratio engines should use hot type spark plugs.
The cooler spark plug is made more sophisticated than ordinary products, so it can ensure the accuracy and quality of ignition when the engine rotates at high speed, thereby ensuring the maximum power at the engine's limit. In addition, its resistance is also controlled to be very small, and the number of flashovers is not lost at all due to the increase in rotational speed. Therefore, using a spark plug with a higher value is of great benefit to getting used to raising the engine speed.