What does the heat range on a spark plug mean?
Spark plug heat dispersal The degree to which a spark plug disperses the heat it receives is called its “heat range”. Spark plugs with a high degree of heat dispersal are called high heat range (cold type) and those with a low degree of heat dispersal are called low heat range (hot type).
Is a higher heat range spark plug better?
A low heat range (or hot) spark plug typically has a long thin insulator nose which will heat up easily however will not dissipate readily to the metal shell (above left). Conversely, a high heat range (or cold) spark plug has a short thick insulator nose which will dissipate heat much easier (above right).
What happens if spark plugs are too cold?
If the tip temperature is lower than 500°C, the insulator area surrounding the center electrode will not be hot enough to burn off carbon and combustion chamber deposits. These accumulated deposits can result in spark plug fouling leading to misfire.
What does running a colder spark plug do?
*When a spark plug is referred to as a “cold plug”, it is one that transfers heat rapidly from the firing tip into the engine head, keeping the firing tip cooler. *A “hot plug” has a much slower rate of heat transfer, which keeps the firing tip hotter.
What happens if you run a colder spark plug?
The biggest problem is that running a colder plug when it isn’t needed, is that it will foul up quickly. This happens because the plug tip doesn’t stay hot enough to burn off the carbon deposits, and so a build up occurs.
What does 1 step colder spark plugs mean?
A modified engine with higher cylinder temperatures will usually need a colder heat range spark plug. Generally, for every 75-100 hp you add, you should use a one (1) step colder heat range to be safe and avoid pre-ignition. The plug gap may also need to be adjusted smaller to avoid misfire.
Do Iridium plugs burn hotter?
Denso Iridium Power plugs feature the heat range at the end of the part number. For example, IK20 has a heat range of 20. Denso plugs get colder the higher the number, hotter the lower the number. Starting with part # IK20 (heat range 20), a colder plug would be # IK22, a hotter plug would be # IK16.