I've been thinking about getting a midpipe for a while. I asked a Mazda tech with a lot of rotary knowledge about it. He recommended against it. He said as soon as a CEL is thrown, which will eventually happen, the 8 would revert to the default fuel map and run rich since it thinks there's a problem. He said that would lead to poor gas mileage but more importantly worse carbon buildup. I've searched the forums and people agree about running rich.

My question is does this make sense or am I over thinking this? Will it really hurt the engine if it's running too rich? FWIW, I don't consider buying an AccessPort to load custom maps as an option.

 

Well if it helps; there are brands that will not throw a light. i personally am running a Rx7store racepipe-no cat or resonator just a straightr pipe and strangely i dont get a light. i rarely get it once in a while but its on for a day and then nothing. i do not have any custom maps or cobb tuner. you will have a stronger odor coming from your car and it will increase the tone. When the light is on, it does go rich and in carbon build up and that i am not too familiar with.

 

Your Mazda tech friend is a typical Mazda tech. He doesn't know ****. The only code(s) you will get if you are running a cat less mid pipe are for the rear O2 and that will not put the ECU into and default mode, limp mode, etc. If you are running a mid pipe with a cat you will (should not) not get a CEL. Some run cat less mid pipes and do not get a CEL but that is rare. Even spark plug Fowlers, and other tricks do not work.

So the only question is, do you want cat less non resonated, cat less single resonated, cat less dual resonated, catted with resonator, catted without resonator, 3", 2.5", do you mind the smell of gas, do you have a sniffer test where you live?

The CEL being on does not make the car run rich. I have been logging for over a year and I have not seen a change in my AF ratios. I have run the SR Motorsports cat less non resonated pipe for the past couple of years and now the rx7store single resonated and I got a CEL with both before I installed the AP and both performed similarly but with the HKS Hi-power both pipes made the car insanely loud. So I just got this yesterday

http://www.flickr.com/photos/9krpmrx8/4968876181/http://www.flickr.com/photos/9krpmrx8/4968876181/ by http://www.flickr.com/people/9krpmrx8/, on Flickr

 

Get the rx7store high flow cat. I've been running it for a couple weeks now with no CEL.

 

lol completely false.
Sounds like a mazda tech lol.

 

Grungepup has the RP supercat on his car and no CEL. You can also order the BHR pipe with a Davesport cat.

 

I plan to get a cat less single or dual resonated midpipe and don't mind the smell. I've got my eye on the BHR midpipe. They don't have emissions tests where I live so that's not a factor. I have 80k on my 8 so I though it might be a good idea to get the midpipe now since my cat is almost out of warranty.

 

Thanks Charles. I've been interested to read the initial reviews.

 

Will you need to run an aftermarket ecu like the accessport or a racing beat flash when running a mid-pipe with a cat-back?

 

^ No, a custom tune is not needed but a custom tune would maximize performance. But many run full header back aftermarket cat less exhaust systems without a custom tune or any aftermarket engine management.

 

@OP check out the video on how the BHR midpipe sounds on youtube.