It's gonna be hard to pass the inspection with the cat off. Although not having the cat will increase in air flow making the car easier to breath, giving it some performance. I actually got a exhaust system but Ima get my car inspected before installing it

 

Damn, I really don't want a performance drop, but I need to pass emissions

 

Yes, the cat will affect performance. It may quiet down the noise a little, but probably not by a large amount.

 

So it will bring down performance by quite a bit? Any other way of passing emissions without it then?

 

Well, a high flow cat won't be as restrictive as a factory one, you'll probably notice something. Can you find a stock cat to install to do emissions, then swap the header back on?

 

I have the stock header and CAT. Just not too car savvy and in a rush to get my car licensed. If I had more time I'd do it myself. Know anywhere in Portland that switch my header/CAT cheap? I live just across the bridge.

 

Not sure how to close a thread but this can be closed. Pass emissions.

 

What did u do to pass?

 

Well I took it in to a performance muffler/exhaust shop to get a high flow CAT. They raised my car and said the previous owner had a customer spacer installed and rewired the O2 sensor so that it thought the spacer was a CAT (when in reality it was just a straight pipe). He said it should pass emissions as it is, as the check engine light was only on cuz my o2 sensor was out, not that it was detecting there was no CAT. Took it in, it passed.

 

Actually the "custom spacer" wasn't custom at all lol. It's the defouler that comes with the header. You're correct that in theory, they are supposed to trick the o2 sensors and make it so it has no CEL. Unfortunately for many rsx owners I've noticed they don't work unless you have a very long defouler. I'd rather help you install the header and cat I gave you than see a great header have a cat welded on, that is if you didn't already do it.

As for the o2 sensors being bad, I was never aware of that, since the kpro I had on there previously (less than a week before sold) had shown no codes for bad o2 sensors. I apologize if thats actually the case.

 

Well good to know! Got passed emissions anyways
And I ran the check engine light code and if says it's the downstream o2 sensor (only code it's giving), which is a cheap fix and honestly not gonna rush to fix it as its not a big deal.

 

Secondary O2 is throwing code because of that header probably. If you had Kpro you could just disable it. The secondary is only used for emissions purposes anyway, so like you said it doesn't really matter.

 

Awesome. Thanks for clarifying. And does a k-pro help run the engine cleaner/smoother or just increase performance?