Video: M3 Valve-Open Cold Start exhaust indoors

[SaMaster14]

Did a short video with perspectives from both inside and outside of the car doing a cold start this morning with the valves open. I think the car sounds amazing! Car was in park and efficient mode (how it always starts up), and I revved to around 2k rpm only. You can hear (both when inside and out) how the exhaust 'calms down' after about 20 seconds. [Both the inside and outside takes were the same start up sequence, just 2 different cameras]

Watch/listen in HD!

(Honestly, the bass is so deep, I think most cameras can't pick up the sound and makes it sound 'broken.' I think my camera on the outside did an ok job...)

[shortseller]

Now I know why my neibhors 6 houses down hear me on cold starts.

Sounds fantastic, it puts a smile on my face every time I hear it. One might even call it euro exotic. Not sure why it's disparaged so much?

Thanks for sharing your proper sound check video.

[chipotle_napkins]

Damn that is loud! Way better than with the flap

[RocketBoots]

I still think the cold start sounds like a diesel truck or lawn mower, even in real life. To my ears, this is true with aftermarket exhausts (vids) as well. But once it gets a little warm, the stock exhaust sounds pretty good. You might be right about the mic's not being able to capture the bass, or that most speakers, or headphones, may not be able to reproduce the proper frequency range. Thanks for trying though

I heard my own exhaust from outside my car recently, and it sounded pretty darn good!

[Falafel Combo]

Originally Posted by SaMaster14

(Honestly, the bass is so deep, I think most cameras can't pick up the sound and makes it sound 'broken.' I think my camera on the outside did an ok job...)

Totally agree, and thanks for making this video! It's sounds awesome!!

[SaMaster14]

Thanks for the comments guys. Glad you enjoyed the video! Tried my best to capture the sound haha

[AnujS2K]

Love it.

I can already hear a complaint coming.

[Xtabi]

Thanks for posting. Sounds great!

[Turbo_435i]

Too loud

[Blindside_137]

Originally Posted by shortseller

Now I know why my neibhors 6 houses down hear me on cold starts.

Sounds fantastic, it puts a smile on my face every time I hear it. One might even call it euro exotic. Not sure why it's disparaged so much?

Thanks for sharing your proper sound check video.

I think its a combination of two problems.

1. Restricted and muffled sounds due to the valves when closed

2. As OP stated, videos really don't pick up the bass notes well

combine those and you have the lawnmower type sounds on youtube that just flat out sound bad. Of course it is better in person but I really think the valves have a lot to do with it and frankly this is why I've never been much of a fan of valved exhausts. They really only sound great when open. But the convenience of having quiet and loud all in one is desirable.

Thanks for sharing Samaster! sounds beefy!

[SaMaster14]

Originally Posted by schybrid

Too loud

I didn't buy an M3 for it to be muffled and quiet...

[MineralWhiteF80]

since you started a cold start thread, here is a quick video I made of my car during cold start with the M Performance exhaust with the flaps open. This video was filmed from approx. 15 feet back using an iPhone 5s.

Everyone within a 2 mile radius of my house is promptly woken up at 7:50 am each morning.

Only thing my video lacks is the heavy, deep bass that you feel in your chest during cold start. When I start it in my garage (car backed in), my organs vibrate for the first 8-10 seconds.

Keep in mind, if you are watching this on a smartphone and listening through the phone's speakers, it sounds much worse than if you listened to it with headphones (or in person ).

[JTmarlin]

Sorry guys, don't have an M4 yet, what do you mean valves/flaps open?

[SaMaster14]

Originally Posted by JTmarlin

Sorry guys, don't have an M4 yet, what do you mean valves/flaps open?

For government purposes (I think) the car has covers/flaps on the exhaust that open and close depending on throttle setting and how hard the car is being driven. When the valves are covered the exhaust is much more muffled. When open (like in the video) the exhaust is much more raw and aggressive.

[Blindside_137]

Originally Posted by MineralWhiteF80

since you started a cold start thread, here is a quick video I made of my car during cold start with the M Performance exhaust with the flaps open. This video was filmed from approx. 15 feet back using an iPhone 5s.

Everyone within a 2 mile radius of my house is promptly woken up at 7:50 am each morning.

Only thing my video lacks is the heavy, deep bass that you feel in your chest during cold start. When I start it in my garage (car backed in), my organs vibrate for the first 8-10 seconds.

Keep in mind, if you are watching this on a smartphone and listening through the phone's speakers, it sounds much worse than if you listened to it with headphones (or in person ).

Wow! You didn't need to idle until the sun went down!

Sounds great!

[Richardzy]

Nice! great video

[Alen E90]

Sounds aaaawwwesome!!

[F80 M Freak]

so the factory default on cold start is valve open?

[pookgai]

Originally Posted by F80 M Freak

so the factory default on cold start is valve open?

No, the factory default on cold start is valve closed. You can mod the car by unplugging the valve motor wires and leaving them permanently open.

[bigsid05]

Originally Posted by RocketBoots

I still think the cold start sounds like a diesel truck or lawn mower, even in real life. To my ears, this is true with aftermarket exhausts (vids) as well. But once it gets a little warm, the stock exhaust sounds pretty good. You might be right about the mic's not being able to capture the bass, or that most speakers, or headphones, may not be able to reproduce the proper frequency range. Thanks for trying though

I heard my own exhaust from outside my car recently, and it sounded pretty darn good!

Generally agree, I think the exhaust sounds pretty good when warmed up with the flaps open but is pretty horrible at cold start.

[bigsid05]

Originally Posted by SaMaster14

For government purposes (I think) the car has covers/flaps on the exhaust that open and close depending on throttle setting and how hard the car is being driven. When the valves are covered the exhaust is much more muffled. When open (like in the video) the exhaust is much more raw and aggressive.

I actually don't think it's emissions related, I think it's to control the sound - it drones a bit <2K RPM with the flaps open and is obnoxiously loud at startup with the flaps open.

[04cobra]

To be perfectly honest, the cold start this car has is probably the main reason I wont keep it long term. I have had loud cars before but I could always leave my house and get out of the neighborhood with them, while still being quite. This thing is just obnoxiously loud for no reason at start up. My whole family wakes up if I leave for work early. I also live in a very quiet neighborhood and feel like a dick in the mornings.