[JoshuaevansF87]

I have a n55 m2 I have the dinan exhaust with the dinan res delete thinking about a down pipe soon just not sure to go sport cat or catless let me know some pros and cons about both

[nioh_lbbm2]

Pros and cons in terms of what?

[JoshuaevansF87]

Originally Posted by nioh_lbbm2

Pros and cons in terms of what?

What's the benefits of choosing one over the other shoulda said it a little differently my bad

[DanG]

Both are illegal. You are not allowed to change the manufacturers smog system. The catted downpipe at least does some smog control. People have complained that catless downpipe causes gas fumes in the cabin.

[nioh_lbbm2]

I know you're new but It's been discussed before. Plenty of knowledge on the forums so do a search next time.


Pros and Cons to a catless downpipe https://f87.bimmerpost.com/forums/sh....php?t=1526092

[Anthony1s]

I wouldn't go with catless because it's ridiculously loud. My ears were ringing after hearing the backfires on a catless m3. You also will have issues passing noise requirements at tracks. They also smell and leave more soot on your exhaust tips.

As far as any aftermarket downpipe being illegal. Maybe it is where Dan lives, but not where I do. My state requires my car to pass emissions, which the Fabspeed does. And also not exceed 88db when traveling <35mph, and not greater than 92db when >35mph. Of course, your local county or HOA may have different rules from your state, so check those too.

[Slowphiveo]

I went with the Fabspeed sport cat and loved it when I had mine. No tune required and no CEL.

[BostonM235xi]

Catted DP 💯👍🏻

[6speed_M2]

Catless no question