[//M]

This too

[azibux1]

On a related note... Is there any way to guarantee the exhaust valve to be open at any one time? ... to unplug it and force it to stay open - is my reasoning

I tried today but I couldn't actually work out if it was open or shut in various modes at idle, it all felt / sounded the same at idle so I didn't want to unplug it of course while it was shut as that would be worse.

The valve is just round the bend in the exhaust so you can't see it either... Hmmm

[Aloha Joe]

Originally Posted by boostm3

Stick a decibel meter on that puppy.. Ive got zero difference with ASD deleted via harness, but stock downpipe.

Your post has made me doubt my hearing, as I’m just several months shy of 60. So to make sure I didn’t have to go to the ENT doc, I downloaded a decibel app to my IPad. Here Is what I’ve learned.

I placed the IPad, 3 feet behind and just to the outside of the drivers side exhaust. I did that just for the ease of getting in and out of the car to check readings.

At initial cold start up, the app gave me a reading of 123-128 db.

I then took it for a 15 minute drive to get the engine warm.

I returned to my garage and placed the Ipad in the same location in reference to the car as before.

Car in neutral (6mt), comfort mode at idle, app gave me readings of 80-82. Stepped on gas and got rpm’s to 3,000, readings went up to 92-94.

Sport mode in idle, readings came back 87-90. At 3,000 rpm, readings were 99-102.

Then changed the mode to sport plus, I got basically the same results as sport mode.

I then went back to comfort mode and repeated the process one more time to verify. I got basically the same results as the first run. So in my little scientific test, the sports modes in the M2 have an increase of just around 9% versus comfort mode.

Once again, I do have the Fabspeed d/p, with no tune, stock muffler. Also not sure if I moved the Ipad to the passenger side exhaust, if the results might have been even larger. I’ll leave that test for another day.

[Aloha Joe]

Originally Posted by GregoryK

My point is that the engine map remains the same. The steeper throttle response can make the engine sound different but the reality is that if hit the peddle to the floor in any mode without the ASD the sound will be similar.

Please see my post above. While I can’t give you the technical reason why it’s louder in sport. I’d suggest after you get your M2, code ASD off and try driving in an enclosed parking lot with the windows down and in different modes. This is where I first realized sport mode has a louder volume than comfort. From inside the car with windows up, it’s hard to tell.

[boostm3]

Originally Posted by Aloha Joe

Your post has made me doubt my hearing, as I’m just several months shy of 60. So to make sure I didn’t have to go to the ENT doc, I downloaded a decibel app to my IPad. Here Is what I’ve learned.

I placed the IPad, 3 feet behind and just to the outside of the drivers side exhaust. I did that just for the ease of getting in and out of the car to check readings.

At initial cold start up, the app gave me a reading of 123-128 db.

I then took it for a 15 minute drive to get the engine warm.

I returned to my garage and placed the Ipad in the same location in reference to the car as before.

Car in neutral (6mt), comfort mode at idle, app gave me readings of 80-82. Stepped on gas and got rpm’s to 3,000, readings went up to 92-94.

Sport mode in idle, readings came back 87-90. At 3,000 rpm, readings were 99-102.

Then changed the mode to sport plus, I got basically the same results as sport mode.

I then went back to comfort mode and repeated the process one more time to verify. I got basically the same results as the first run. So in my little scientific test, the sports modes in the M2 have an increase of just around 9% versus comfort mode.

Once again, I do have the Fabspeed d/p, with no tune, stock muffler. Also not sure if I moved the Ipad to the passenger side exhaust, if the results might have been even larger. I’ll leave that test for another day.

Joe, it almost sounds to me like your ASD is still active. On the ASD threads, its pretty universally accepted that the loudness we hear in the cabin when we switch from Comfort mode to Sport mode is a fabrication of ASD and doesnt exist without it.. I dont have your DP so I suppose its possible that has something to do with it although Im not sure as I dont see how it would make a difference in drive mode sound differentials. I really have no explanation of what youre hearing unless ASD is still, at least partially active in your car.

Also, I have the Technic PNP harness installed as my method of ASD deletion.. I wonder if that would make a difference. Yet, Ive heard from many who have coded it out instead, and theyve confirmed that the noise increase they used to hear going from comfort to sport is strictly a function of the ASD module and doesnt exist without it. Quite the mystery.

go figure!

[akkando]

Originally Posted by boostm3

Joe, it almost sounds to me like your ASD is still active. On the ASD threads, its pretty universally accepted that the loudness we hear in the cabin when we switch from Comfort mode to Sport mode is a fabrication of ASD and doesnt exist without it.. I dont have your DP so I suppose its possible that has something to do with it although Im not sure as I dont see how it would make a difference in drive mode sound differentials. I really have no explanation of what youre hearing unless ASD is still, at least partially active in your car.

Also, I have the Technic PNP harness installed as my method of ASD deletion.. I wonder if that would make a difference. Yet, Ive heard from many who have coded it out instead, and theyve confirmed that the noise increase they used to hear going from comfort to sport is strictly a function of the ASD module and doesnt exist without it. Quite the mystery.

go figure!

If the mic is outside the car next to the exhaust it's not ASD.

[AndrewC1989]

Originally Posted by azibux1

On a related note... Is there any way to guarantee the exhaust valve to be open at any one time? ... to unplug it and force it to stay open - is my reasoning

I tried today but I couldn't actually work out if it was open or shut in various modes at idle, it all felt / sounded the same at idle so I didn't want to unplug it of course while it was shut as that would be worse.

The valve is just round the bend in the exhaust so you can't see it either... Hmmm

you can force open/shut it with this phone app: http://bimmerlink.com/

or you can buy a CG valve controller for $200

[boostm3]

Originally Posted by akkando

If the mic is outside the car next to the exhaust it's not ASD.

Yup... Missed that wrt mic location. I have no explanation for what Joe is hearing/measuring. Many of us seem to have no sound differentiation between drive modes after ASD is removed except for exhaust over run pops and crackles.

[azibux1]

Originally Posted by andrewc89

you can force open/shut it with this phone app: http://bimmerlink.com/

or you can buy a CG valve controller for $200

Thanks I saw that but don't have an iPhone and didn't want to spend $200 lol

Wanted a free way of getting it open, then unplugging it while it is open

But I can't seem to figure out when it is open or shut just by looking / listening as at idle / a few revs it sounds fairly similar to me

[boostm3]

Originally Posted by Aloha Joe

Your post has made me doubt my hearing, as I’m just several months shy of 60. So to make sure I didn’t have to go to the ENT doc, I downloaded a decibel app to my IPad. Here Is what I’ve learned.

I placed the IPad, 3 feet behind and just to the outside of the drivers side exhaust. I did that just for the ease of getting in and out of the car to check readings.

At initial cold start up, the app gave me a reading of 123-128 db.

I then took it for a 15 minute drive to get the engine warm.

I returned to my garage and placed the Ipad in the same location in reference to the car as before.

Car in neutral (6mt), comfort mode at idle, app gave me readings of 80-82. Stepped on gas and got rpm’s to 3,000, readings went up to 92-94.

Sport mode in idle, readings came back 87-90. At 3,000 rpm, readings were 99-102.

Then changed the mode to sport plus, I got basically the same results as sport mode.

I then went back to comfort mode and repeated the process one more time to verify. I got basically the same results as the first run. So in my little scientific test, the sports modes in the M2 have an increase of just around 9% versus comfort mode.

Once again, I do have the Fabspeed d/p, with no tune, stock muffler. Also not sure if I moved the Ipad to the passenger side exhaust, if the results might have been even larger. I’ll leave that test for another day.

After pondering this for many hours, and doing some of my own testing, I will confirm I have no change in exhaust or engine sound between drive modes such as was present with ASD. .. However, I think i might know whats going on.. Standing still with a warm engine, if you put your foot on the go pedal and get the rpms up to around 2k, for example in Comfort mode, and hold those rpms steady, and switch to Sport mode, you will in fact hear more sound out of the exhaust. However, that would only be because Sport mode is more throttle responsive and, hence, raises the rpms above that which youll have in Comfort mode given the same throttle position. You'll see the rpms rise on the tach as you do this if you wait a few seconds. Higher rpms, higher noise.

I'm guessing it could be nothing more than that . The takeaway is that with ASD enabled, even at idle with no throttle tip in, switching from Comfort to Sport raises the cabin noise with no increase in RPMS.. That would be ALL ASD responsible for the noise and the volume of the fake sound would only be heard in the cabin.

If thats not what's happening in your case, Im afraid Ill have to give up and just give in to the fact that your car unlike many other M2s behaves differently.

[tux2005]

I was under the impression that the general consensus was that the modes DO affect whether the valves are open, comfort has the valve closed except with aggressive throttle while sport and other modes would have the valve open at all times.

So if you're pushing hard, then the sound would be the same regardless of modes.

But yes, ASD is the most drastically affected by the driving modes.

[GregoryK]

I find this discussion super interesting! Are you guys saying that there is an exhaust valve that is opened and closed by the driving mode switch on the stock exhaust system? This would be the only possible reason for Joe's readings.

[boostm3]

Originally Posted by GregoryK

I find this discussion super interesting! Are you guys saying that there is an exhaust valve that is opened and closed by the driving mode switch on the stock exhaust system? This would be the only possible reason for Joe's readings.

Yea, thats what's being claimed. I for one have never heard an exhaust difference from changing drive modes; only ASD fake noise difference.

[Aloha Joe]

Originally Posted by GregoryK

I find this discussion super interesting! Are you guys saying that there is an exhaust valve that is opened and closed by the driving mode switch on the stock exhaust system? This would be the only possible reason for Joe's readings.

Originally Posted by boostm3

Yea, thats what's being claimed. I for one have never heard an exhaust difference from changing drive modes; only ASD fake noise difference.

I’m not claiming that the valves are open, tux2005 brought that up. I posted earlier that I don’t know the technical explanation of why my exhaust is louder in sport than comfort, but it is and it’s not just opinion.

I re-did the db test with my ipad again today with very similar results as I posted earlier. On average, comfort mode was about 1 db closer to sport today versus Sunday’s test. The difference in the 1 db difference could be attributed to the location of my ipad not being in the exact location as Sunday.

Please keep in mind, my tests were done with the ipad approx 3 feet from the exhaust and just to the outside on the drivers side. The difference is literally only about 8-9% louder on my tests. It’s nowhere near the 30+ percent versus a cold start, so please don’t think it’s a drastic change.

[boostm3]

Originally Posted by Aloha Joe

I’m not claiming that the valves are open, tux2005 brought that up. I posted earlier that I don’t know the technical explanation of why my exhaust is louder in sport than comfort, but it is and it’s not just opinion.

I re-did the db test with my ipad again today with very similar results as I posted earlier. On average, comfort mode was about 1 db closer to sport today versus Sunday’s test. The difference in the 1 db difference could be attributed to the location of my ipad not being in the exact location as Sunday.

Please keep in mind, my tests were done with the ipad approx 3 feet from the exhaust and just to the outside on the drivers side. The difference is literally only about 8-9% louder on my tests. It’s nowhere near the 30+ percent versus a cold start, so please don’t think it’s a drastic change.

Joe, if its not the valving, which I dont think it is, what then? Did you give my explanation any credence wrt the rise in rpms due to more aggressive throttle mapping when going from Comfort to Sport mode being the cause of your increased volume measurments?

[Aloha Joe]

Originally Posted by boostm3

Joe, if its not the valving, which I dont think it is, what then? Did you give my explanation any credence wrt the rise in rpms due to more aggressive throttle mapping when going from Comfort to Sport mode being the cause of your increased volume measurments?

As mentioned in my earlier posts, I’m not the one who brought up valving and I do not have a technical explanation, but the results is what it is. And yes I do give respect to your post unless I wouldn’t have done 4 tests, However in idle with rpm’s being identical, why would sport be louder than comfort? Or am I not understanding your question correctly?

[GregoryK]

Check these threads.....about the valve.

http://f87.bimmerpost.com/forums/sho....php?t=1277527

http://f87.bimmerpost.com/forums/sho....php?t=1340967

Think this explains Joe's numbers...

[Who's on first]

Originally Posted by WAY

Does Sport and MDM have the same exhaust note?

MDM has nothing to do with anything except traction items.

Unless it's different then all the other M's. Which I doubt.

[boostm3]

Originally Posted by GregoryK

Check these threads.....about the valve.

http://f87.bimmerpost.com/forums/sho....php?t=1277527

http://f87.bimmerpost.com/forums/sho....php?t=1340967

Think this explains Joe's numbers...

I dont think so. The first link is referring to the pops and crackles on exhaust overrun which is definitely more pronounced in Sport+ mode and MDM. And the second link refers to valving wrt cold starts, and some other observations that dont prove much.

All I know is that since ASD delete, switching between drive modes makes no difference whatsoever on my M2. All this said with a ymmv proviso. Maybe its the downpipe Joe has; maybe its the coded vs harnessed ASD delete method which might have an influence on exhaust valving. Maybe its the model year of the M2. Im not doubting what he is hearing and measuring, and Im not doubting what Im hearing. There must be an explanation for the difference; I just dont know what it is at this point. The whole connection between ecu controlled exhaust valving and what exactly happens between drive modes is a bit of a mystery.

[sh_kross]

Originally Posted by Who's on first

MDM has nothing to do with anything except traction items.

Unless it's different then all the other M's. Which I doubt.

I won't say if it's different than other M cars, but the exhaust note on overrun is very different on traction mode. I don't know and can't verify if there is anything else different other than that and the traction settings, though.

[Who's on first]

Originally Posted by sh_kross

I won't say if it's different than other M cars, but the exhaust note on overrun is very different on traction mode. I don't know and can't verify if there is anything else different other than that and the traction settings, though.

When we code Euro MDM... it all has to do with traction items. I've never seen anything in the coding for MDM at all for anything else.

[sh_kross]

Originally Posted by Who's on first

When we code Euro MDM... it all has to do with traction items. I've never seen anything in the coding for MDM at all for anything else.

Like I said, I can't verify if it modifies anything else. But, there is a very noticeable audible difference between Traction and Comfort, and arguably any other mode. Now, I don't know what that means, but the audible difference is there.