Heat Ranges
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The Mercedes-Benz M276 comes with Bosch spark plugs, which have a higher heat rating than NGK.
The term “colder spark plug” or “hotter spark plug” refers to the range of speed that the spark plug(s) will transfer heat from the tip of the plug. A colder spark plug will transfer heat quicker and faster than a hotter spark plug, which will transfer heat a lot slower. The end goal / result is to keep the cylinder temperatures as cool as possible. However, by running too cold of a spark plug, the plug to “foul out”, whereas if you were to run too hot of a spark plug, the result can be severe engine damage.
Heat Range Reference Chart
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Recommendation
NGK: 95875