Matt, There are several things that can make the catalytic converter go bad. Most often it's when it glows from running to rich and the precious metals that coat the block as it's called are burned off. My new performance catalytic converter has larger diameter holes for more free flow and it's legal to remove the old one and replace it with the new updated one. John Hervey www.specialtauto.com -----Original Message----- From: dmcnews@xxxxxxxxxxxxxxx [mailto:dmcnews@xxxxxxxxxxxxxxx] On Behalf Of denverdelorean Sent: Tuesday, September 20, 2005 2:28 PM To: dmcnews@xxxxxxxxxxxxxxx Subject: [DML] Legal or Tampering? Just to let you all know. It is apparently just as illegal to modify the exhaust system into a dual configuration with two, free flow cats To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/