Ya in Cali its Illegal to modify any Emission part. But as long as you don't get popped for a Smog Inspection and can just do a Smog test Id think it would pass with a catted X pipe. Luckily I live in one of the Few it not only county in California that doesn't require Smog testing. So im good to go once I can afford the Headers and X pipe.
2011 3.7L MT, Magnaflow Competition Axle Back Exhaust