Does the pipe add a bit of noise for real? I’m guessing the stock one is baffled to keep cabin noise to a minimal?
There’s a little bit of high pitched whistling - it’s sort of like the sound in the video I posted but probably 3 octaves higher. It’s not really noticeable - I’ve just spent so much time on “sound design” with my car that I’m highly attenuated to it. If I can find my lav mic I’ll try to grab an underhood sound bite.
I’m guessing the double baffle in the stocker creates a little toroidal vortex that breaks up the air enough to kill the noise. I just like turbo noises

I do think it spools a little faster too. I noticed that if I stomp the gas in second the tires slip for a moment, I don’t think it did that before. Not more power, but it came on quicker.