Just got all my new stuff for my Evo from MAPerformance and AMS. My cat delete however has no 02 bung. Do I just get one welded on? I also got a vibrant 02 extender to help against cel's but once again, do I even need it now? I believe I need to mark it and get a bung welded on but I wanted to ask the experts. I plan to ask my tuner too but hes not open till Monday. Thanks guys

 

No point in having one welded on unless your catback doesn't have it. Check your catback to see if there is a bung there, chances are there is one already.

 

Yes you should have one welded on so you can use the CEL fix. If you plan on going WB at any point, have them weld a second one for the future.

 

You could just get or borrow a Tactrix cable and disable the CEL couldn't you?