i ordered 2.25" piping from kteller, and its still on its way, but before having it put on at muffler shop, i also want to replace my 170k old cat with a carsound, but on ktellers website when adding the cat to the cart, it asked the option of "o2 bung both F&R", "o2 bung front", or "o2 bung rear"??? and since i did'nt know i could'nt add it to the order.

basically i just need a carsound cat that attaches to 2.25 piping on the out side and attaches to my stock pipe on the in side? and don't know about bungs and ****, lol, so does anyone know for a 90 crxsi which carsound is the right model that would fit for what i mentioned above? i want to order it soon if possible, thanks for any replies

 

no bung needed.
Ryan