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      03-28-2020, 03:24 PM   #1
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Ok so I figured I'd start a new thread here vice continuing the discussion in the thread I started about lowering springs.

So I just did the mod on my M850i to leave the exhaust valves in the open position and man on cold start does it sound so much better. Didn't get a chance to take it for a drive yet but I'm already happy that I did it.

Best part was also that it took me about all of 15 minutes to do so.
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      03-28-2020, 06:00 PM   #2
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Originally Posted by Da808dad View Post
Ok so I figured I'd start a new thread here vice continuing the discussion in the thread I started about lowering springs.

So I just did the mod on my M850i to leave the exhaust valves in the open position and man on cold start does it sound so much better. Didn't get a chance to take it for a drive yet but I'm already happy that I did it.

Best part was also that it took me about all of 15 minutes to do so.
how did you do it?
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      03-28-2020, 06:29 PM   #3
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Originally Posted by Resjudicata View Post
Quote:
Originally Posted by Da808dad View Post
Ok so I figured I'd start a new thread here vice continuing the discussion in the thread I started about lowering springs.

So I just did the mod on my M850i to leave the exhaust valves in the open position and man on cold start does it sound so much better. Didn't get a chance to take it for a drive yet but I'm already happy that I did it.

Best part was also that it took me about all of 15 minutes to do so.
how did you do it?
With the valves open (and the car off of course), all you have to do is loosen the plastic rear guard under the bumper. Each side has 5-6 bolts that hold the plastic guard up.

Once that's loosened you have access to the solenoid and harness that controls the valves in the exhaust. Just unplug the harness from the solenoid which is held in by a tiny little clip. Tape up the harness connector to protect it from the elements and tuck them away nicely on the side.

Reinstall the bolts you removed holding the plastic guard. Repeat this for the other side.

Get in car start her up and give her a few revs and listen to how good it sounds.
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      03-30-2020, 11:09 PM   #4
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Originally Posted by Da808dad View Post
With the valves open (and the car off of course), all you have to do is loosen the plastic rear guard under the bumper. Each side has 5-6 bolts that hold the plastic guard up.

Once that's loosened you have access to the solenoid and harness that controls the valves in the exhaust. Just unplug the harness from the solenoid which is held in by a tiny little clip. Tape up the harness connector to protect it from the elements and tuck them away nicely on the side.

Reinstall the bolts you removed holding the plastic guard. Repeat this for the other side.

Get in car start her up and give her a few revs and listen to how good it sounds.
Sounds easy and something I'd like to do. Any chance you can provide some pics of the plastic rear guard and wiring harness/solenoid needed to do the work? I can tear apart a PC like no tomorrow but cars just scare me as not my domain. I'm afraid without a visual guidance I'll end up at the dealer claiming absolute ignorance to my F'd up attempt.
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      03-30-2020, 11:39 PM   #5
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Quote:
Originally Posted by bloozemanAZ View Post
Quote:
Originally Posted by Da808dad View Post
With the valves open (and the car off of course), all you have to do is loosen the plastic rear guard under the bumper. Each side has 5-6 bolts that hold the plastic guard up.

Once that's loosened you have access to the solenoid and harness that controls the valves in the exhaust. Just unplug the harness from the solenoid which is held in by a tiny little clip. Tape up the harness connector to protect it from the elements and tuck them away nicely on the side.

Reinstall the bolts you removed holding the plastic guard. Repeat this for the other side.

Get in car start her up and give her a few revs and listen to how good it sounds.
Sounds easy and something I'd like to do. Any chance you can provide some pics of the plastic rear guard and wiring harness/solenoid needed to do the work? I can tear apart a PC like no tomorrow but cars just scare me as not my domain. I'm afraid without a visual guidance I'll end up at the dealer claiming absolute ignorance to my F'd up attempt.
Here you go. Sorry these are the best pics I could get right now. Had to run outside real fast right before dinner. Lol.

Sorry for the crappy writing on the pic. Lol. This is the drivers side of the car but the passenger side is exactly the same just opposite.

Let me know if this helps or you need better pics.

Only tool needed is a 8mm socket wrench. Honestly there really is no way to mess this up unless you don't grab the harness by the small clip and end up ripping it out. The small clip comes off real easy though so shouldn't take much to get it off.
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      04-01-2020, 08:09 PM   #6
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Hi - I was informed this will trigger a cel. Please let me know if you have a cel light on.

Thanks
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      04-01-2020, 08:59 PM   #7
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Originally Posted by bmwbeast View Post
Hi - I was informed this will trigger a cel. Please let me know if you have a cel light on.

Thanks
***knock on wood*** It hasn't after 3 days of driving the car since I did it.

I did this same thing for my old M3 from the first day I got the car and it never triggered a CEL for the 4 years I owned it.
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      04-01-2020, 09:07 PM   #8
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Originally Posted by Da808dad View Post
Here you go. Sorry these are the best pics I could get right now. Had to run outside real fast right before dinner. Lol.

Sorry for the crappy writing on the pic. Lol. This is the drivers side of the car but the passenger side is exactly the same just opposite.

Let me know if this helps or you need better pics.

Only tool needed is a 8mm socket wrench. Honestly there really is no way to mess this up unless you don't grab the harness by the small clip and end up ripping it out. The small clip comes off real easy though so shouldn't take much to get it off.
Thanks for the pics as definitely helpful and the tip on the harness. Last question and I'll claim complete ignorance how do I know the valves are fully opened before doing the procedure with the car off? I'm going to assume if I start the car, take it for a quick spin in Sport Plus and park it in the garage the valves are fully open at that point. Correct?
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      04-01-2020, 09:32 PM   #9
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Quote:
Originally Posted by bloozemanAZ View Post
Quote:
Originally Posted by Da808dad View Post
Here you go. Sorry these are the best pics I could get right now. Had to run outside real fast right before dinner. Lol.

Sorry for the crappy writing on the pic. Lol. This is the drivers side of the car but the passenger side is exactly the same just opposite.

Let me know if this helps or you need better pics.

Only tool needed is a 8mm socket wrench. Honestly there really is no way to mess this up unless you don't grab the harness by the small clip and end up ripping it out. The small clip comes off real easy though so shouldn't take much to get it off.
Thanks for the pics as definitely helpful and the tip on the harness. Last question and I'll claim complete ignorance how do I know the valves are fully opened before doing the procedure with the car off? I'm going to assume if I start the car, take it for a quick spin in Sport Plus and park it in the garage the valves are fully open at that point. Correct?
Yes, just look inside the outer tailpipe on each side. You can see if the valve is open or shut. In the pic (circled in yellow) you can see the valve and it's in the open position. If it was closed you wouldn't be able to see past it as the valve would prevent you from seeing further into the tailpipe.

Just make sure you don't do it if the tailpipes are hot as it's possible you may brush up against them, depending on how big your hands are, when unplugging the harness.

*disclaimer* I'm not responsible to car or bodily damage. Lol.
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      04-01-2020, 09:57 PM   #10
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Quote:
Originally Posted by Da808dad View Post
Quote:
Originally Posted by bloozemanAZ View Post
Quote:
Originally Posted by Da808dad View Post
Here you go. Sorry these are the best pics I could get right now. Had to run outside real fast right before dinner. Lol.

Sorry for the crappy writing on the pic. Lol. This is the drivers side of the car but the passenger side is exactly the same just opposite.

Let me know if this helps or you need better pics.

Only tool needed is a 8mm socket wrench. Honestly there really is no way to mess this up unless you don't grab the harness by the small clip and end up ripping it out. The small clip comes off real easy though so shouldn't take much to get it off.
Thanks for the pics as definitely helpful and the tip on the harness. Last question and I'll claim complete ignorance how do I know the valves are fully opened before doing the procedure with the car off? I'm going to assume if I start the car, take it for a quick spin in Sport Plus and park it in the garage the valves are fully open at that point. Correct?
Yes, just look inside the outer tailpipe on each side. You can see if the valve is open or shut. In the pic (circled in yellow) you can see the valve and it's in the open position. If it was closed you wouldn't be able to see past it as the valve would prevent you from seeing further into the tailpipe.

Just make sure you don't do it if the tailpipes are hot as it's possible you may brush up against them, depending on how big your hands are, when unplugging the harness.

*disclaimer* I'm not responsible to car or bodily damage. Lol.
I had to do something similar but I did it on day one; here are the steps:
1. Step inside car
2. Start it
3. Then the mechanical piece...

Name:  01585796310.jpeg
Views: 1800
Size:  394.3 KB

I know, I know--I'm a first-class dick... so my wife says anyway. The only tool involved here is me.

Last edited by limeypride; 04-01-2020 at 10:03 PM..
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      04-01-2020, 11:14 PM   #11
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Ok thanks - I’m going to try it. Is there a difference in sound when driving or just at start up?
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      04-02-2020, 01:23 AM   #12
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Originally Posted by bmwbeast View Post
Ok thanks - I'm going to try it. Is there a difference in sound when driving or just at start up?
Honestly I don't know if there is a difference while driving. I didn't drive the car home from the dealership before I opened the valves and since this is my wife's car I've barely driven it at all period. Lol.
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      04-02-2020, 01:26 AM   #13
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Quote:
Originally Posted by limeypride View Post
Quote:
Originally Posted by Da808dad View Post
Quote:
Originally Posted by bloozemanAZ View Post
Quote:
Originally Posted by Da808dad View Post
Here you go. Sorry these are the best pics I could get right now. Had to run outside real fast right before dinner. Lol.

Sorry for the crappy writing on the pic. Lol. This is the drivers side of the car but the passenger side is exactly the same just opposite.

Let me know if this helps or you need better pics.

Only tool needed is a 8mm socket wrench. Honestly there really is no way to mess this up unless you don't grab the harness by the small clip and end up ripping it out. The small clip comes off real easy though so shouldn't take much to get it off.
Thanks for the pics as definitely helpful and the tip on the harness. Last question and I'll claim complete ignorance how do I know the valves are fully opened before doing the procedure with the car off? I'm going to assume if I start the car, take it for a quick spin in Sport Plus and park it in the garage the valves are fully open at that point. Correct?
Yes, just look inside the outer tailpipe on each side. You can see if the valve is open or shut. In the pic (circled in yellow) you can see the valve and it's in the open position. If it was closed you wouldn't be able to see past it as the valve would prevent you from seeing further into the tailpipe.

Just make sure you don't do it if the tailpipes are hot as it's possible you may brush up against them, depending on how big your hands are, when unplugging the harness.

*disclaimer* I'm not responsible to car or bodily damage. Lol.
I had to do something similar but I did it on day one; here are the steps:
1. Step inside car
2. Start it
3. Then the mechanical piece...

Attachment 2273599

I know, I know--I'm a first-class dick... so my wife says anyway. The only tool involved here is me.
I don't think my M850i has that button. I wonder if that's specifically for an M8? I would think that if there's a button for it on the M8 that maybe it's a setting you can code out via Bimmercode?
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      04-02-2020, 01:48 AM   #14
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Quote:
Originally Posted by Da808dad View Post
I don't think my M850i has that button. I wonder if that's specifically for an M8? I would think that if there's a button for it on the M8 that maybe it's a setting you can code out via Bimmercode?
Ooops, I was being naught but a light-hearted facetious Brit (aka. me )... and assuming there wasn't given the effort put into resolving this--surely someone would've seen it, right?

On the coding aspect: hmmm, it's possible. As a software engineer, I'm leaning towards unlikely, though, since you'd either 1) need to remap some other key or 2) change its inherent default value to 'always open'. The latter is wayyy more likely than the former... again, just opinion--I didn't write any of this stuff. If it can be solved through coding (and that term is a *massive* overstatement of what coding actually is and what it's capable of affecting), it's more likely through something unconstrained like E-Sys than Bimmercode but, even then, it's a matter of discovery vs. complexity--a true needle in a planet-sized haystack of key-value pairs.

Short story: I wouldn't hold you breath but it's not dead from the outset either (it's probably starting to smell a bit, though ).
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      04-02-2020, 09:20 AM   #15
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he's being a tool. that exhaust button is very specific to m8 only. The m850i doesn't have it or anything like it. it's not possible, it's hardware like the m buttons on the steering wheel.

it can only be done in the m8.
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      04-02-2020, 09:32 AM   #16
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Quote:
Originally Posted by Resjudicata View Post
he's being a tool. that exhaust button is very specific to m8 only. The m850i doesn't have it or anything like it. it's not possible, it's hardware like the m buttons on the steering wheel.

it can only be done in the m8.
I thought it was funny.

And that's a self-proclaimed tool if you please—per my post.
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      04-02-2020, 01:03 PM   #17
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I just tried this and all I can say is Wow! The car sounds deeper and louder when starting. Give it a couple of revs
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      04-02-2020, 04:28 PM   #18
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Originally Posted by bmwbeast View Post
I just tried this and all I can say is Wow! The car sounds deeper and louder when starting. Give it a couple of revs
It's pretty good for such an easy mod to do. Although not as easy as limeypride push of a button easy.
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      04-04-2020, 08:36 PM   #19
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Quote:
Originally Posted by Da808dad View Post
*disclaimer* I'm not responsible to car or bodily damage. Lol.
LOL #1 of the thread as just catching up.


Quote:
Originally Posted by limeypride View Post
I thought it was funny.

And that's a self-proclaimed tool if you please—per my post.
LOL #2 of the thread as I got it instantaneously as no such option on our lowly M850i's hence the entire subject of the thread.
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      04-04-2020, 08:57 PM   #20
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Quote:
Originally Posted by bloozemanAZ View Post
LOL #1 of the thread as just catching up.




LOL #2 of the thread as I got it instantaneously as no such option on our lowly M850i's hence the entire subject of the thread.


Slightly off-topic (OK, totally) but do you guys have that lovely crystal shifter?
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      04-04-2020, 10:03 PM   #21
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Originally Posted by limeypride View Post


Slightly off-topic (OK, totally) but do you guys have that lovely crystal shifter?
I do as my wife fell in love with it during a test drive so although I didn't plan on it in my build I got it to appease her. The lady whom runs the office for my detailer said she loved it too. Mat Watson in his 4 month test of a M850i with it (great video) says he's in love with the chintzy and wished they wrapped the whole shifter in it vs just the top.

My favorite unsuspected aspect of it is for 12 minutes after you shut to car off (similar timing for the console USB jack and 12-volt plug) it glows an "8". Ironically I was just out in the car doing some testing of my Valentine 1 Gen2 against the Gesture Controls LIDAR camera to respond by to a guy whom is seeing different results with his and a 540i with Gesture Controls. Hence, I knew it would be lit up and took the pick through the windshield. Guess I love a bit of chintzy too.
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Last edited by bloozemanAZ; 04-05-2020 at 05:45 PM..
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      04-04-2020, 10:31 PM   #22
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Quote:
Originally Posted by limeypride View Post
Quote:
Originally Posted by bloozemanAZ View Post
LOL #1 of the thread as just catching up.




LOL #2 of the thread as I got it instantaneously as no such option on our lowly M850i's hence the entire subject of the thread.


Slightly off-topic (OK, totally) but do you guys have that lovely crystal shifter?
Yup, we have it on ours.
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