[Azines]

I've tried searching all over for this subject, but just want to get a clear answer and some feedback. I have a 2012 BMW 335i Xdrive E92 Msport, and it currently has a Charge pipe, Intake, and a JB4.

I've been looking into downpipes and was eventually thinking to go catted because of the noise and fume smell, but I heard somewhere that the Xdrive model comes with secondary cats, would that negate the fume smell on idle and make the sound less raspy?

Also, I know the JB4 auto deletes the CEL code for the DP, but is the DP fix needed in case of emissions? Or would the JB4 along with the secondary cats be enough to pass an OBD II test?

[Impreza98]

Also curious about this. Bump for an answer.

[Evilchef71]

I have a 2011 xdrive with AR catless and yes there are secondary cats, it still sounds great and I really haven’t noticed any smell. Go catless you won’t regret it!

[Azines]

Originally Posted by Evilchef71

I have a 2011 xdrive with AR catless and yes there are secondary cats, it still sounds great and I really haven’t noticed any smell. Go catless you won’t regret it!

Thanks Evilchef! How long have you had this setup? And I might be mistaken I heard it somewhere can't recall though, will removing the downpipe cats burn out your secondary cats eventually, or is that not an issue?

[carguy138]

Care to share how you are making it through the annual inspection?

[Azines]

Originally Posted by carguy138

Care to share how you are making it through the annual inspection?

The car can pass emissions testing with ctless DP with a DP fix from BMS, if your state has OBD testing, however it will fail the sniffer test. I was just curious if the secondary cats on the XI are enough to make the car in a ready state for emissions, or is the DP fix still required

[carguy138]

Originally Posted by Azines

The car can pass emissions testing with ctless DP with a DP fix from BMS, if your state has OBD testing, however it will fail the sniffer test. I was just curious if the secondary cats on the XI are enough to make the car in a ready state for emissions, or is the DP fix still required

Yea I am aware of that. It's only OBD inspection and you are allowed to have one "not ready".

From what I can see about the DP fix on the N55 requires tapping wires and I'd prefer not to do that. Had APR software on a A4 with a high flow cat (essentially catless) and it passed every time.

Was wondering if MHD would work in the same way.

[iwantaw335]

I don’t know about secondary cat but I’m pretty much straight pipe with PE mod and I don’t have any smell.

[Evilchef71]

Originally Posted by Azines

Thanks Evilchef! How long have you had this setup? And I might be mistaken I heard it somewhere can't recall though, will removing the downpipe cats burn out your secondary cats eventually, or is that not an issue?

I’ve been running this way for about 10 mos and am very happy with the sound- aggressive but not obnoxious or raspy. I haven’t heard about “burning out” secondary cats but I’m not sure why that would be the case. The VRSF DP fix should take care of you cats being “ready” or complete for inspection but we don’t have a sniffer test in my state so I dunno....