Dear Forza Community,
Perhaps I am going insane or losing my hearing, but is anyone else hearing the BOV whistle (or more like a sudden discharge of pressure) from some of the NA cars every time you shift? My McLaren F1 does it and so does my stock Ferrari 250GTO. After upgrading the Cams, Intake Manifold and the Exhaust of my GTO, then sound became less consistent. I thought maybe my TV isn’t out-putting the sounds correctly, so I set Forza to Home Theater and turned on the surround sound. Same thing. Anyone else experiencing this?
Here’s a hot lap video someone else posted. If you listen carefully, you can hear the sounds at 1:02, and again at around 1:24 (I’ll see if I can find better examples of it)
inconsistant blow of valve sound? I would assume that it would more likely be Exhaust pops.
I assumed that, as well, but with the audio properly cranked up on the surround system, the two sounds are completely distinguishable. You can hear it around 1:01 in that video, but not very well. I don’t know what other NA cars do this, other than the McLaren I tested, so I haven’t found a good example of it yet. Shifting basically sounds like a sudden release of pressure, both at low RPM and high. If my memory serves me correctly, the sound was more noticeable in cock-pit.
Like Wonderpill says its more than likely backfire you can here. My 250 defo dont dump, sounds pretty amazing through its pipes though!
Where is this video?
You sure it isn’t just the flywheel?
Whoops! Forgot to post it 
I added it to the OP. It’s not the best example of the sound, but I’ll see if I can find more. It sounds really loud on my speakers at home.
I believe the sound you are hearing might be the intake noise from the car. I’ve noticed this sound myself on certain N/A cars. The miata is notorious for making this sound when you put the racing cold air intake on it. Its a different sound though than the blow off valve but it is a whooshing type sound.
