Our '11 335i had a ton of passion when we first bought it...lots of burble and pop. Even some seriously cool backfires. But then they updated the software in order to fix a window programming problem (didn't fix it). That update took away the passion and screwed things up big time.
That ill-fated update increased fuel economy at the expense of being emasculated. Several bad things happened:
- The throttle response was instantly deadened. I compare it to when I put it in reverse...the computer deadens the throttle response on purpose (I'm guessing as a safety precaution). It's fine for reverse, but in 1st gear in a BMW? On a subsequent visit to service, they cleared the adaptations, which helped a lot.
- Whenever I backed off the throttle, the revs would stay at 2k for several seconds. That's just wrong. If I back off the throttle, I expect it to return to idle. If someone can tell me a reason why this should be normal, I'm listening.
- When we bought it, it felt like about 95% of the feel of the 335is we didn't buy. We really enjoyed the very Indy-like or F1-like double exhaust pops between every 1-2 or 2-3 shift. But after the update, the beautiful exhaust sounds all but disappeared.
The PPK brought it all back, for the most part. So far, We're liking it.
Under hard acceleration, there's definitely a difference. Very noticeable. I don't drive it too hard, but on on-ramps and highway speeds, the extra oomph is noticeable.
There's more low-end resonance. The day I got it back, it was raining and I couldn't tell much difference. But once the skies cleared and the top went down, I could tell the difference. It seems slightly deeper at idle, and under normal acceleration, seems a little deeper too.
There's so much burble under "engine overrun conditions", that it almost sounds too fake. Back off the throttle and the burble kicks in for 1.5 seconds, then stops. Every single time. As the revs keep going down while coasting to a stop, I can make it burble all the way down the block just by blipping the throttle (even just a little bit), but that seems a little stupid to me. Formerly, it would occasionally but unpredictably burble all the way down the block until I stopped, without any input from me. Anyway, the point is, the passion is back to its passionate self, with 20 extra horses to boot. We are very happy with the PPK.
BTW, I **highly** recommend Nick Alexander Imports for this. Their deal is $699 installed. Best service ever, seriously.