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 or zip tie the sensor in a corner? 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

 

Bag it and zip tie it out of the way. The only reason for a rear NB O2 is to check the cat is working. With no cat you don't need the NB O2. If you are running Tephra V7 9653XXXX you can disable the CEL or disconnect it completely and run the O2 sim to fool the ECU into thinking it's still there.