How to pass emissions without a catalytic converter?
 

Just picked an RX-8 and plan on installing a full exhaust which will remove the cat. I live in an area which has yearly emissions and besides switching the cat in/out every year what other easier options do I have?

I’ve been reading about using a defouler on the secondary sensor with mixed results. I’ve also read about using something like MazdaEdit to remove the codes, but that’s an expensive option just for removing codes.

Any input is appreciated!

Thanks!

Pay off the tester? That's about the only way. Even if it's not a sniffer test, you can smell an uncatted rotary a mile away.

If it is a sniffer test swapping in a cat is about all you can do. If you can afford it, get a high quality high flow cat from HJS as part of your exhaust build.

Do your emission test first before you put in the midpipe for sure. There is no other option than to swap the cat back in for yearly emissions testing unless you can bribe them (I don't recommend it). You can also remove the codes with an OBD2 scan tool. The code that will pop up from time to time is P0420 Catalyst low but I just clear it every time it pops up every couple days. Cheaper than MazdaEdit that's for sure.

If I clear the code with a scan tool, drive a few cycles before the CEL turns on again, and then drive directly to get my emissions is there a chance of the code not being thrown and me passing the emissions? If so, is there a certain number of cycles I should drive to put all the sensors in “readiness” mode and before the CEL is on?

There's no way to know when the CEL will come back when you clear the code. Sometimes it stays off for only a day, sometimes it stays off all week. Even still, you won't pass emissions ever with no cat installed. They check your exhaust and even the dumbest guy there will be able to tell you have no cat just by smelling the exhaust gasses and hearing the excessive noise it will make.

Yes if you clear it, you'll need to wait whatever number of cycles the car needs to get to readiness again... Which will the pop the code. So there isn't an easy answer here, except having a cat.

Depends on what exactly is included in the emissions test where you are.

No, won't work. Emissions computer will detect the code or the system "not ready". Your options are pretty much below.
Buy the editing tool
Buy a high flow converter
Replace the converter before each inspection
Keep your car tuned properly and run with the original converter.
Find someone to inspect your car under the table (not advocating this course of action).

I recall BigCajun actually passed once without a cat. He mentioned that the guys there thought the resonator is a cat... I don't know how this kind of stuff can happen, and I wouldn't count on it.

Another solution people haven't mentioned: move to a place without yearly inspection, LOL.

Just buy an OEM mid-pipe with a good cat from a junkyard for pretty cheap. Yeah swapping is kinda annoying but such is life.

Depends on where you live, bribing can become a pretty big deal. I know that there were people who tried to bribe the driving test examiners here in BC, Canada and that landed them some jail time. I don't know if inspection people count as government official and how your laws work for it, but if it doesn't go well(which is likely), I'd bet that you are in much bigger trouble than not passing emissions.

I definitely won’t go down the road of paying off the inspector.

The headers are long-tube headers from BHR, so I can’t just swap in the mid-pipe with a cat. I’ll need to change back to the exhaust manifold and then use a midpipe with cat (either stock or BHR midpipe/cat). This is a more involved install back and forth and part of why I’m dreading to do the labor on it. I know another option is to get Racing Beat’s headers and then much more easily swap the midpipe every year.

Anyone know if there is much of a performance difference between the BHR long tube headers VS Racing Beat headers with open midpipe??

If I go the route of getting a tuning module, is the MazdaEdit the one to get? I would only need it to remove the codes. I don’t plan on changing any of the stock tune parameters.

BTW, they only plug into the OBD2 port here in Georgia.

Oof.
 

Here in Cali I’m pretty sure the fine is 10k and probably loosing license if the smog guy gets caught cheating a test. I’m about to have Rotary PowerUSA swap a REW in a month or so and will be discussing emissions with them before the process gets rolling.
Best of luck man, just get used to swapping pipe and laying it! 😎

if the inspector is semi competent, they will do a visual and see there is no cat. and that is before hooking up any equipment. maybe you can try the jedi mind trick on them.

Yes, but it was visual only, no OBD or sniffer.
The time before that they didn't even lift it.
Missouri.
One of the reasons I hesitated about the BHR header.
I really wanted it, but I didn't want to have to take it off ever.