i don't know what this says about missouri's emissions test or my focus . but my car passed the obd test with NO cat and a full "race" header instlalled. since my car is newer than a '96, missouri doesn't throw it on the rollers. they just do a obd reading and check the gas cap. i know the seller claimed the header would pass emissions, but i was planning to throw down some tricks or install the oem stuff if all else failed. woohoo!