Xpipe vs test pipe E90 M3

[Azurefire91]

Hello all,

I am sure this topic has been beat to death but there were tons of results whenever I would try and find information and it was a bit overwhelming, Long story short I recently installed a valvetronic exhaust on my E90 M3, The sound is good as is but honestly I would rather be much louder and more exotic sounding with valves open. What can be done to acquire this without deleting primary cats or having a CEL? I am not willing to hack up the stock exhaust system and I live in california so catless is pretty much a no go because of the headache. I am not really familiar with xpipes or test pipes or midpipes so recommendations would be greatly appreciated!

[sdbmwcoding]

Originally Posted by Azurefire91

Hello all,

I am sure this topic has been beat to death but there were tons of results whenever I would try and find information and it was a bit overwhelming, Long story short I recently installed a valvetronic exhaust on my E90 M3, The sound is good as is but honestly I would rather be much louder and more exotic sounding with valves open. What can be done to acquire this without deleting primary cats or having a CEL? I am not willing to hack up the stock exhaust system and I live in california so catless is pretty much a no go because of the headache. I am not really familiar with xpipes or test pipes or midpipes so recommendations would be greatly appreciated!

Test pipes: remove primary cats and will trigger CEL

X pipe has 2 versions: there are full x pipes which bolt onto the headers and all the way back to the muffler, majority of these will have the cats deleted or at least the primary cats and they will trigger a CEL which you don't want.

Options 2 would be other x pipes on the market that hook up to the stock primary catalytic converters. This would mean you'd retain the stock primary cats which would mean no CEL and they'd most likely remove the resonators and secondary catalytic converters (removing these does not trigger a CEL) or sometimes they just remove the resonators or secondary cats and retain one or the other. I don't know the x pipe names that retain the stock primary cats off the top of my head, I'm sure there's others here that can chime in and further clarify but hopefully this will break it down for you to further understand the setup options.

[Azurefire91]

This is incredibly helpful, I am not against deleting secondaries and resonators I just did not want to remove primaries and deal with Smog/cops/CEL afterwards. Anyone who can refer me to companies that just remove the resonators or the resonators and secondaries would be great! Thanks sd*********!!

[wyatth]

^ Challenge Street.

[Azurefire91]

wyatth,

I will look into this one! looks to be what I might be looking for, will it give an exotic raspy sound or more of a V8 grumble? I prefer the high rasp of something along the lines of gintani

[wyatth]

Removing cats and resonators will make it louder and raspier, so it's probably up your alley.