Well, I finally got around to getting my NA Rx8 emissions tested today, and to my surprise Maryland has gone completely over to OBD II testing for emissions with cars newer than '96. I drove in, paid a few dollars, they plugged me in, and I drove out. This started me thinking...

I've been planning to boost my Rx8 with a BHR/MM turbo kit whenever they finish making it, but I've seen a few heat damage related threads with turbos and cats. I know a number of you run straight pipes with your turboed 8s. Would a high flow metal center cat be able to handle the heat/pressure of a turboed Rx8 or is a straightpipe really the safest way to go.

I know the AccessPORT can suppress/clear CELs, but will that be detectable by the OBD II test, and how illegal is that exactly? Are we talking felony here or misdemenor...

I would prefer to spend some extra money to buy a high flow metal cat that will keep the air clean, but I absolutely don't want the bottom part of my car lighting on fire due to it. Any thoughts?

 

I had an RP Supercat, loved it N/A. Then, I turboed my car and it died in possibly the worst way. I had it punched out this morning and the honey comb had kind of sunflowered/heat warped so that it was clogging the exhaust pretty badly. The cat went from functional to throwing a code within 1000 miles of going turbo. The Supercat used a metal catalyst and was a pain to hollow out. A cat might survive a well-tuned turbo car, but you won't be immediately well tuned post installation. I have no real advice, but that's my story.

 

i got the GReddy turbo kit with a MM tuned AP and RP high-flow cat. i thought i needed it for emissions as well, but apparently my car is too low so they just waive me. either they're too stupid to realize that my car is OBD II or they just don't care. who cares right? i'm good to go.

i'm thinking about going straight without the cat now. i put it on in June 2008 and have probably put on 2500 miles on it. no problems at all.

 

Yeah, thats what I'm worried about. I think with MM tunes and the AccessPORT I will have a decent tune eventually, but I've seen a lot of people with slagged cats after going turbo and I'm even more worried about body heat damage etc than just melting the cat. I don't really know what options I have though... I do my best to stay on the right side of Johnny Law because my job requires it, so I'm curious what options I have besides a high flow cat.

Dan, we met at the College Park Tuning event right? Were you the blue with the Greddy kit? I actually had a bunch of questions for you about your install etc if so. You are using the RP high-flow now and you aren't having any problems? Any specific reason you would go to straight pipe if the cat is handling well?

 

yep, that was me. only reason, power.

 

i did that with my 3 rotor rx7. the problem is cat vs no cat changes the tune, especially at part throttle.

kind of a catch 22 situation.... at least with the rx8 you can monitor cat inlet temp...

 

Since the stock cat is probably ceramic would that be able to better handle the hotter exhaust? I'm guessing not. But then if you had a HiFlow and then added the Turbo Kit and got it tuned would if be okay? Or is this only a problem when adding a hiFlow after tuning has already been done?

I live between California and Idaho a lot, Idaho has no smog at all, but if I ever go to Cali Permenantly I don't want to have a headache trying to get my emmisions straightend out.