97 S14 Catalytic Converter Options

[Btaztic]

Hello everyone,

So I have 2 questions here.

My 1997 S14 is originally from Missouri. I live in California, and the previous owner had it registered here before me. I barely passed my last smog check, and was told that my catalytic converter might need replacement and that I had an exhaust leak.

Fast forward, I had the catback 5zigen exhaust replaced, as it was rusting through, with a APEXi N1 ExTi catback.

I was going to change out the catalytic converter the same time I had the exhaust changed. The cat I’m referring to is the one right before the second O2 sensor is, right before where the exhaust mounts up. Come to find out what I thought was a catalytic converter is actually just a hollow pipe that LOOKS like a catalytic converter, but really isn’t. The guy at the shop said because my car is a “federal car” that I have to have the exact stock cat on the car unless I may not pass smog, he wasn’t sure though.

So I just asked him if he can check it out and see how bad the “fake cat” looked, I didn’t know it wasn’t actually a real one by this point. When he took it off we found out it was hollow and he had to weld it back to the downpipe looking piece that actually holds the real catalytic converter because part of it had broken off its so old.

I left everything as is and only had the exhaust replaced. I just found out that cars not in CA have only one cat, which is the one at the top of the down pipe, and cars originally in CA have 2 according to this thread.

http://zilvia.net/f/showthread.php?t=328695

Here is where S14DB said “Federal cars have only the primary cat. California (CARB) cars have a secondary cat." If this is true, it would make sense, since my car is from Missouri.

Now my car exhaust is making like a rattling noise around where the fake cat is located. It sounds like metal grains or something are kicking around in there, and it only happens on start ups, and when pulling off from a stop, low rpms. It did not do that prior to having the exhaust changed.

Now my questions are and the first one sounds kinda obvious but 1) If I replace the fake cat with a universal real cat, I should be able to pass the smog still since it would be a 50 state carb legal cat, right? I don’t see why I wouldn’t be able to. And/or 2) Should I I just replace that whole piece with and CA OEM part that houses both catalytic converters instead?

I want to eliminate that noise and and still pass smog, even though come to find out that my car has been passing smog no problem with just one cat. Just shows how stupid these CARB laws are.

TL/DR - Replace fake cat with universal CARB cat? Or replace with a CA OEM part that houses both cats instead?

[afishysilvia]

Depends completely on the guy you go to for smog, and how much they are checking and inspecting all of your hardware. I have no cats, straight piped but because I’m willing to deal with the risk and money associated with it. Pm me if you need help.

[Btaztic]

That is true. Thanks man! I want to try to limit my risk as much as possible lol. My car is damn near stock and I've already been pulled over twice in Glendale
With that being said, I want to be draw as little attention as possible.