Catalytic converters

@Jarlaxle Here is my .1% right (and most of my wrong): "....watch out for removed smog control parts which
were perhaps legal, or quasi-legal to remove some places so long as the
emissions met local standards. In CA (and in many other states as well) the
smog test includes a visual equipment check: certain emissions-control
components must be installed and functional, regardless of the outcome of
the tailpipe test (my jetting misinformation). The tailpipe test is not CARB specific but the visual check is per my research. I had to put a preheater hose on a set of headers on a 67 Mustang to get my neighbors 'stang to pass the very crude smog rules of 1968. It still had its stock 302 2bbl intake but those headers sure helped that car, pretty snappy even with wide tires on the back.

>> there was a post on a guy buying a 49 state Mistu 3000GT without EGR, he said he had to get an EGR (non functional) to put in place of the factory cover and then it passed Cali smog visual. the sniff test was not affected but if the smog checker tested the EGR (manually pushed the pintle out to see if the idle raised) and it raised the idle (vacuum leak) it was considered working even thought the vacuum lines went nowhere.