I’ve recently learned that the precats on the Spec V’s can start failing and hurt the engine, so I want to get headers for my ‘06. But doing research I’m a little confused. I’m new to cars in general, so apologies if this is a total newb question. Where does the spacer go? Some of pictures show...

I live in CA. I now need a smog check in a Star station. I will fail a visual test with my set up having a gutted cat and a non fouler on my second o2 sensor. So I recently bought a aftermarket pre-cat from Eastern Catalytic converter to pass smog, removed the non-fouler unused an on second o2...

i own an 05 spec all stock except for aem short ram. it also has the Nissan certified rebuilt engine which i believe has about 75000 miles on it? who knows. in total, i just rolled over 131000 today, and besides replacing a camshaft sensor, everything is pretty much smooth. but....it still has...

so i'm new to the forums and have a question... i bought my 02 spec about 9 months ago... has 96k miles on it now, is it too late for my precat? i haven't really noticed any signs of it failing but idk.. the thing is i don't know if the owner before me had anything done about it, and i don't...