For Just a term with this sort of outsized importance in motor vehicle society, "JDM" is an acronym for a reasonably tedious phrase: Japanese Domestic Sector. It refers to items built and supposed for sale and use in just Japan (i.e., not for export). This features almost everything from automobiles https://elevemotors.com/product/chevrolet-camaro-ls-16-20-oem-2-0l-turbo-engine-motor/