Porshe996 is right.
I have a 05 with no cats, pertnear straight exhaust. I did install some dynoflow straight through mufflers for tone. The X sounds "SWEET". I race off road with it so it does not matter with the law. My crew says they can hear me coming for a few miles. 5000 rpms from a Nissan 4.0 puts out a distict sound!