Does it ever stop??....plus de flap?

[alexk]

Originally Posted by select

Besides i think if they would manage to reach the filter, BMW would have told people in the manuals.

I can think of at least 10 things that are not written in the owner's manual

The flap is definitely for torque boost in low rpms - fact.
It's not just for noise.
This is also due to the fact that the CSL gives you full throttle control, something that doesn't exist anymore (in other words, when you hit full throttle with 1500rpm, the CSL will open the throttle butterflies to 100%).
If you were controlling/restricting the throttle opening, you don't need a flap anymore (bikes had additional throttle butterflies to restrict airflow then newer generation had controlled/restricted throttle control).
I personally love the full throttle control the CSL gives to the driver.

Not removing the flap due to performance and risk of rain is my opinion and what I do when there is heavy or torrential rain.
If you check the intake when driving with heavy rain and 120-140, we can discuss again. The water can go to the intake.
Each one can decide for their own of course, since they own their cars
I mentioned my point of view since someone asked and I just give facts.