My friend and I are building a 3" single turbo-back system for my car. My question is simple: how can I fit the stock narrow-band o2 sensor to the custom downpipe? I tried to find a nut that would work (to weld to the pipe) but was not in luck. Can I buy these somewhere, and if so what size do I need and where can I get it?

Thanks!

 

google "O2 sensor bung" and you will find what you are looking for

 

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