My solution for running test pipes and passing emissions

[Deebo]

Guys, wanted to share these as I just went through this hassle of a project. I bought my car 6 months ago with test pipes installed, owner included the stock cats but the way all test pipes are cut and clamped, there's no way to clamp the cats back on. I brought the car to a local exhaust shop and had them add a small length of pipe to the stock cats with flanges, and flanges to the test pipe/ exhaust section as well. The pictures describe it better than I can. I now have a setup that's super easy to install every 2 years with just a couple bolts, easier to store than a full stock X-pipe, and I can fit the cats in the car to bring to a shop if it needs to be done. The whole deal cost me $200 with labor, if you're having test pipes installed I'd recommend having this done from the beginning! Once the stock cats are in, flash back to stock and drive the car for a couple days to get all the emissions monitors into ready state.

[derbo]

your other option is to do Vband exhaust connectors at the end of the test pipes and OEM cats.

https://motoiq.com/project-e90-m3-pa...xhaust-tips/3/

[Deebo]

Exactly! Your way is what I originally brought the car in to get, but the shop didn’t have V-band clamps on hand and preferred to do it this way. Nicely done!

[Mvy]

Good ideas! Nicely done.

[bmwlover0725]

Great idea if you live in CA. I'm lucky enough to be in NY (no that this state's laws are much better). I've been waiting for someone to do this exact setup for a while. Very nice job.