I plan on outfitting my car with some headers in the future, and i want to change the y-pipe also. Awhile back one of my cats clogged so i had both of them chopped out and some pipe welded back in for a temp fix. My question is has anyone had any trouble with emissions people noticing that your dual cat car has only one cat on it? Or do they only look to see if it has a cat to begin with. Plan was to get some hooker headers with y-pipe into a single cat. Im wondering if the emissions people have something that tells them this car should have 2 cats not 1.