E46 330i Decat

I finally took the plunge and had my car Decatted last week thanks to German Technik in EL I had all 4 cats removed, 2 in the manifolds and the 2 mid cats. The pipes were cut open, cats removed and welded back together so everything still looks stock.











After a week of driving catless I must say the difference in terms of performance before and after is night and day. The car is much more responsive throughout the rev range, but more especially in the lower rev range. The car overall feels a lot smoother and accelerates a bit faster off the line. I would be really interested to see what sort of gains I've gotten out of this on a dyno.

Interestingly enough we noticed that the post cat sensors on my car are blanked off for some reason, I only have pre cat sensors before the manifold cats so it hasn't stored any fault codes or brought up the engine light. The first day or 2 after the cats were removed it did have a bit of a rough idle, not enough to stall though, but that was due to the ECU adapting because we reset all the adaptations after decatting so it just needed some time to adjust.

In terms of fuel consumption I think it's roughly the same if not a tad better than before under the same conditions, but I think it's still too early to tell if there's a significant difference. I will update on that after 2 or 3 tanks.

I'm told that the car sounds really nice outside, but I personally find it sounds very raspy above 3000rpm in the cabin with the windows down. With the windows up I don't hear it at all. I should maybe get someone to drive my car so that I can hear for myself how it sounds

All in all I think it's the best money I spent on the car and would definitely recommend it to get some extra power and responsiveness out of your car

Big thanks to Yuben for the advice off forum