JCC_90

Hello, I’m James, long time lurker on here. Really appreciate all the help this site has given me over the years. Wish I listened to everyone here more with my first 05 rx8. I’m now on my second, swore I’d treat her better this time. So I’ve read through what I could find with my issue on here and I still could use some further direction.

I have an 04 rx8 with 78k on it. Previous owner took immaculate care, just a garage kept weekend car for
him. Got it with 62k on it. I’ve never flooded the engine, I regularly use idemitsu premix when I fill with premium/super, coils and plugs admittedly are over due…

I’ve started losing significant power can’t rev past 6k, CEL P0420, 95% sure my cats clogged…

I can’t weld, so I was gonna get a cat with pipe from onlinemazdanparts.com for 1200 before shipping (1300 after). Then I had a thought that, I’ll just burn that one out premixing too.

So I’m thinking my best option would be to find a used cat with resonator (maybe on here :wink: :wink because I gotta pass Jersey inspection, like yesterday’s ago. Then just buy a decat for around 200ish to keep on there till next inspection.

Does the latter make more sense than getting a new OEM cat?

Is their an aftermarket cat w/ resonator that will pass a sniff test? That will still keep my price lower than 1300 (including the 200 for a decat to swap to after inspection)

trying to keep my cost as low as possible given I’m only working part time now and I’ll most definitely need to be replacing/upgrading my coils and plugs ASAP after i take care of this.

thanks for reading all that if you did…help please? Any advice on the best route to take would be great. I’ve been looking for smog test info for NJ but can’t seem to find any specific requirements and not sure how to tel from specs if an aftermarket will pass the test.

Shaozhou Zhang

Teamrx8 has been using HJS cat with success (IIRC rated for 1050 centigrade). But I heard that it is a race only application, do a research on this and if you can't find anything sent him a PM.
Use cat only for inspection is also a go, it will smell terribly.

JCC_90

Yeah I’ve done a little bit more reading and I’m thinking I want to find a HJS 200cpi cat, shop said they’d weld it onto my existing pipe for around 200 and I read on here hon can get the hjs cat for about 500-600.

I just can’t find where to buy one. not sure how to tell if it is 200cpi or 100cpi either. And Idk how to tell if its got a spot for the 02 censor or not.

could anyone provide a link for where I can buy a hjs cat that’ll fit? The oem cats are back ordered apparently so that’s not an option for me at the moment either.

thanks again…currently walking and taking trains in south Jersey till I get this worked out…so any help is appreciated. Trying to avoid buying an aftermarket that’ll just burn out.

peloponisios

HJS has a 200cpsi cat which is euro6 rated! But it 's gonna cost you a LOT!
Check their site, check their universal tuning lineNr. 90 95 0190 model.
It's an overkill. Now, there's some swedish racing cat also on ebay, they're claiming their metal is swedish steel. But I have no idea if it stands. Redback converters. Significantly more economic. I don't know anything else about them though.