My catalytic converter is toast. I get the sulfur smell and a bit of black smoke on hard acceleration out of the exhaust. I am SC'd w/ after-market header and AEM EMS, so I'm confident that I have very little chance of getting this replaced under warranty. The $800 price for an OEM cat, seems a bit high, so I'm wondering what other alternatives (besides test pipe) there are. Any good after-market cats? I'm guessing installation is pretty straightforward--just pop out and replace the whole section between header and exhaust.

Second, since I'm only at 55k miles, I'm guessing that my tune is either too rich or too lean through all or some of the power band. Does this make sense? I'd rather spend a couple hundred now to get the tune cleaned up so I don't have to replace the cat again in a year or two.

Thanks in advance!

 

I would guess that you're running rich but I have no direct experience with tuning or even a cat failing. I agree however that the oem cats are overpriced somewhat. There are some after market cats (and some jdm ones if you want) that will flow as good as, or slightly better than stock. I remember reading a post a month ago or so that mentioned a 70mm high flow cat that could be a good replacement for you since you are supercharged. For a good after market high flow cat you should be looking at around $400 or a little less.

 

The high flow cat sounds good to me Do you happen to remember the brand? Or maybe a link to that post? I tried searching, but the results weren't all that helpful.

 

http://www.randomtechnology.com/honda.html

Random tech makes one, however keep in mind that after market cats are not legal in CA and may have to follow specific rules for other states. Check local laws first if you want to be 100% legal, I think there is some sort of stipulation that if your cat dies and it is recorded by a garage then you can legally replace with an after market one that meets regulations, but that is just what I remember and may have been ramblings by someone on a thread here.

 

Thanks for the info. I'll probably call a local shop about the legal details.

 

There was a comparo and our cat is a high flow cat. It's actually higher flow than the other "high flow cats" for sale except one brand, I think.

You're likely running rich and toasted the cat.

It happened to me too. Except the honeycomb broke off and decapitated my secondary O2 sensor.

There are threads where this has happened to stock S2k's as well. There is a thread with a picture of the rattling cat.

 

If I took it in to Honda it'd have cost: $800 for the cat, $300 for the O2 sensor (IIRC), and probably a couple hundred for labor.

 

That's NOT what I did. Suffice it to say, I now have a working OEM cat and secondary O2 sensor for under $150 total... PM if more details requested.

 

Pretty sure that the feds regulate this and require any car less than 10(?) years old to replace cats w/oem ones. The fines are also quite high for both the car owner and however put the cat on, which in a DIY situation would allow them to double fine you, I believe. Anyway, I'm running off of some stuff I read a couple of years ago, so I could be wrong, but if you are looking for legality, junkyard a part is prolly your best option.

Andrew

 

find a local that has a stock S thats willing to help you aout. swap cats and have them warranty it on his car. shady stuff but just an idea.