Anyone know what year cars first started having catalytic converters installed on them? I'm sure Ca. was first in requiring them. I think most States required them in '68 but I don't know when Ca. first required them? I want to buy an old car and don't want the smog equipment on it as it reduces the power alot. I guess I could buy a pre '73 as they are no longer required to be smogged and remove the equipment, but then I'm still stuck with a lower compression engine which is something I don't want either. I tried Google and couldn't find what I was looking for, so I'm hoping someone here will know.