[Rbcmima]

Originally Posted by BigRon033

None of the B-series engines have blow-off valves, so you're going to be subjected to a bit more compressor noise compared to prior engines (N55, N54, ect).

I've heard so many people refer to the "Blow off valve" with this car and wasn't sure if there actually even was one. Thanks for clarifying.

[xcelir8bmw]

Noticed it too. Turbo. Normal.

[Shal28]

Originally Posted by Rbcmima

I got this too, couple days after installing the Dinan CAI, was pretty concerning. If you post a video of the sound then I can compare mine to it and tell you if its the same. Kinda sounds like a hollow echoey sound.

Edit: https://vimeo.com/738043999

For some reason mine sounds like a hissing noise