I’m sure they will ‘fit’ lots of things…..possibly even your car but that isn’t the issue with sparkplugs.

I think I’m right in saying that sparkplugs were one of the first things to be standardised in the aviation (or automotive) world; this is the reason that these American sparkplugs will have a metric thread!

The issue with sparkplugs is fitting the correct ‘rating’ of plug and that really means fitting the plug that will remain at the right temperature while the engine is operating; different ratings of plug transfer heat away from the electrodes at different rates and so the plugs operate at different temperatures. It is important to get this operating temperature right as it has a huge impact on the efficiency of the plug and the replacement interval.