California cars generally emit exactly the same as any other American car. Back when emissions standards were coming into effect, there were "California cars"

California cars generally emit exactly the same as any other American car. Back when emissions standards were coming into effect, there were "California cars" with separate emissions equipment. That was because said emissions equipment was expensive and unreliable. Today, almost all US sold cars conform to CA emissions, regardless of where they are sold. Sometimes you will see cars or trucks with the option for CA Emissions, but this does effect power or performance, it just has different parameters for determining when to trigger check engine lights for emissions-related issues. Though, heavy duty truck can be equipped with an emissions exemption. I think this is, ironically, limited to government vehicles.