Originally Posted by JoeRogan
So you can install this and an aftermarket exhaust like the FSWerks Stealth and keep all the cats in their original location? That's pretty much the most important thing for me when it comes to modding the emissions system as CA is pretty strict on the visual inspection. And I know from another thread there seems to be some confusion about whether PZEV or any other Foci have different cats
yeah there is no way that will pass in california, no cat is illegal at the fedreal level, but unless the car was impounded for some other reason they would never know.
That being said in some states, not cali, an aftermarket hi-flow cat would be enough to be legal, though you would lose most of the benefit of the new headers.
Are you going to dyno soon? thanks for testing this out first.