estland 3 Posted February 3, 2016 I have a decatted xu9jaz engine and it's a bit too loud. Does replacing the back box with a non-cat one make exhaust quieter? Share this post Link to post Share on other sites
Miles 331 1 Cars Posted February 3, 2016 All the GTi back box's are the same in theory, just the manufacture is the difference, Make sure the centre box is OK as well Share this post Link to post Share on other sites
estland 3 Posted February 3, 2016 Thanks for the answer Share this post Link to post Share on other sites
