I'm currently having a mid pipe custom made by a local exhaust shop and I was just wondering what problems I'm going to run into. Will the CEL still come on if I plug the o2 sensor into the straight pipe? I've done this one many other cars with different problems occuring. Has anyone done this before? My pipe pipe is going to be 3" piping and I also have to rx8store 3" cat back installed. I've heard that some people recommend that you use the factory cat back with a mid pipe. Is there any truth that this will produce more power? This just doesnt seems like it makes since to me but this car is kinda wierd and different when it comes to producing those extra horses. Let me know if anyone has any advise, comments, or questions. I hope to dyno this baby as soon as I can.

Thanks,
Jamie

 

If you plug the (second) O2 sensor back in to your empty pipe, it will produce a CEL for 'cat insufficiency', meaning no catalyst activity detected.

Previous posters have found no 'fail-safe' or 'limp mode' situation, just the CEL.

Even if you don't plug it back in you would probably get the same code, so don't even bother putting a flange in for it.

S

 

You would lose power by going back to the OEM cat-back. The issue is how loud your car will be without the restriction of a cat...

 

ok that's what I thought would happen with the CEL but I have put straight pipes on other cars with no prob. As for the cat back, It makes sense that I would lose power witht the stock exhaust one but I heard others talking about it being better or something.

Jamie

 

The cat isn't costing you that much power. As complicated as these 8's are, I would never remove the cat without putting one back on it.

 

Well I just got my baby out of the shop and let me just say that it is freakin loud. When I first drove it, it sounded like a little ricer civic or something. After driving it a while I noticed it calming down and becoming a more aggressive tone. It sounds so nice and quiet until you floor it then it sounds like a 747 taking off. It's completly silent at idle too. Oh and once I ran it for about 5 mins and then raced a mustang my friends behind me said that it shot flames about 2 foot out everytime I shifted at redline. I cant really say I'm pleased with the CEL being on, but I've got a dummy sensor on the way so that'll cure that problem. Now I'm trying to find a stock mid section so I can have it just in case something happens and I need to go to the dealer for something.

I plan on having it tuned and dyno'd here soon and I'll post those as soon as I get them. Oh when I first got on the gas it could instintly tell a big difference. The toruqe loss that some people were complaining about is yet to be found. I can feel an increase in rear wheel spin on demand. Even my friends noticed it when he drove it. It'll be interesting to see how much of a difference it really did make on the numbers though.

Oh if anyone has a factory mid pipe let me know how much you would take for it.

Thanks,
Jamie

 

Looking forward to seeing the Dyno results. Lets us know man!