downpipe questions

[Redrocketms3]

i have been thinking of getting a downpipe and midpipe for a while and have a few questions...

1. will a new downpipe make my engine light come on?
2. what does it mean when a downpipe is both upper and lower?
3. will a test pipe and downpipe combo allow me to pass emitions?

thanks guys for the responses

 

[MS3inDC]

ooo! ooo! can I? huh? can I do it?!


(flame2)

 

[MS3inDC]

(thought)



(google) is your friend!!

 

[Jackis]

First - you should understand, why people are getting new DPs... They want to get rid of restrictions in exhaust system, and the main two are catalytic convertors. They remove them - they can have more power but more problems. CELs, smoking issues, so on so on. If you are going for it - be ready to deal with future troubles.

1. About CEL - it depends... I have catless DP and so far no CEL at all. But it is seldom to have catless DP and getting no CEL.
2. Mazdaspeed front exhaust part (right after the turbo) has 2 main pieces: first converter with 2 oxygen sensors and second converter. First is called "upper downpipe", second is called "race-pipe", "test-pipe", "mid-pipe", whatever... Together they are called "downpipe" or "long downpipe".
3. It depends on the emissions quotes, but generally - no. You can get catted downpipe (long downpipe I mean), from COBB for example. In some of countries or states it may help. I can say that here in Russia we have such a bad emission standards (Euro-2, while all the Europe uses Euro-4,5), that I passed them even with catless DP.

Hope that helps. But the sir above is also right - it was all said billion of times.

 

[FrequentFlyer]

If you have emissions testing where they stick a sensor in your tailpipe and "sniff" your polution levels, you will FAIL. If it's like here in NJ where they plug into the OBDII port and read your codes, you will PASS if your ECU is not throwing emissions related codes, which it shouldn't be, even with a DP. There are downpipes with cats and without. To avoid these issues, I have a Corksport downpipe going in soon and will be removing my racepipe to reinstall my stock midpipe (with cat). The stock downpipe is the most restrictive piece of the exhaust system, other than the actual manifold itself, so replacing that will get you good gains. The difference between having a full catless system vs. having a cat in the pipepipe is probably worth about 5-8whp. To me, it's just not worth the hassle and honestly don't enjoy polluting. In Jersey, the inspection stations do a "visual" with a mirror under the car. I'm not quite sure what they're looking for, but I'm assuming they look for stuff like neon lights and exhaust modifications (like no cats). It's pretty easy to see a straight pipe under the car where a cat should be. They can't see the cat on the downpipe.

 

[MSMS3]

OP: Please, without me ending up sounding like a hard ass, please use the search function. If you find it hard to use, then use Google with your search phrase including "mazdas247" without the quotes. That will tell Google to search this forum for what you are looking for.

I could write several pages trying to answer your questions, and without knowing your level of understanding and experience, that might not prove helpful to you. And there are dozens of threads here already on all of your questions.

I love my catless dp/rp. It is a very serious power mod. it is not for everyone.

Try searching and come back with any remaining questions.

 

[Redrocketms3]

thanks guys for the help.