Matt1276

Does anyone know if a stock cat will fit with my aftermarket exhaust system? I failed my smog test and have to get a stock cat to replace my Hi-Flow Cat. I have a DC Sports 4-1 header and Comptech catback Exhaust sytem. Also, does the stock cat need an O2 sensor when re-installed? (the guy at the Muffler shop is asking in order to order the new cat for me)

purplegsr

What year integra do you have (94-95 have one O2 and 96-01 had 2), and is the header a JDM ITR DC 4-1 or the USDM DC 4-1?

EDIT: ok, I looked at your bio, since you have a 1997, it is an OBD2 computer, which uses 2 o2 sensors - one in your header, and one in your cat. So you will need a stock cat and there should be an o2 in the cat and the header bung. Theoretically, you should already have an o2 in your highflow cat, and as long as it isn't damaged, you could reuse it.

Also, yes, a stock cat will bolt up to your DC 4-1 and your 2.36 in comptech exhaust, as long as it is not the DC 4-1 JDM ITR version. The collector on the USDM one is 2 inches, while the ITR one is 2.5, so if you have the ITR you would need a cat with a 2.5 inch flange.

Matt1276

thanks for the reply and all the info., sounds like it will fit o.k. I have the standard DC-4-1 and a Jackson Racing Cat now and it passed Smog last time. I will be installing the new Stock Cat tomorrow and then back for Smog Pre-test to see if I pass.