Spark plug article

Kendog 170 said

I was reading a spark plug article online. I have always use champion plug 12 heat range so never tried a hotter or colder plug. I found this interesting as different plug manufactures have different heat indexing.
Quote from article.
It is also important to note that Champion plugs use a larger number for a hotter plug while NGK plugs reference heat in the opposite direction, with hotter plugs using a lower number. So, it's important to know your spark plug manufacturer's reference numbers regarding heat range.

Just throwing this out there.

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Yeah, it can get kornfrooshin sometimes going from one brand to another and the dingbats at these parts stores know absolutely nothing about it, so don't rely on them. Maybe one of us can work up a list if there's not already one out there with different brands and how they measure from hot to cold. I knew some were backwards from others, but I don't know which are which with all brands. AC Delco, for instance is hotter the higher the number. Like an 43 plug is colder than a 45. IMO, they all should standardize to that, because it makes more sense, but they don't.