[mjr24]

So I just got rid of my AMG GT53 because it's slow and I hated it and needed to get back in a M. I have a M8 GC Comp. coming in a couple weeks.

I had an exhaust valve controller on my AMG (it had the performance exhaust option) that I actually had to wire to each plug on both sides of the exhaust. You can't just tie those off as it throws a CEL on AMG's. When I had my F90, I was able to just tie them off once they were open.

Now, on the AMG, apparently the flaps were never 100% open unless at full throttle. The performance exhaust option only opens them like 50% I've heard. Hence, the controller module I had was able to open them 100% of the time.

Is it the same on the M's? Does the exhaust flap not ever open all the way except at full throttle? If so, I might be inclined to get a controller instead of tying them off.

[__AD__]

Originally Posted by mjr24

So I just got rid of my AMG GT53 because it's slow and I hated it and needed to get back in a M. I have a M8 GC Comp. coming in a couple weeks.

I had an exhaust valve controller on my AMG (it had the performance exhaust option) that I actually had to wire to each plug on both sides of the exhaust. You can't just tie those off as it throws a CEL on AMG's. When I had my F90, I was able to just tie them off once they were open.

Now, on the AMG, apparently the flaps were never 100% open unless at full throttle. The performance exhaust option only opens them like 50% I've heard. Hence, the controller module I had was able to open them 100% of the time.

Is it the same on the M's? Does the exhaust flap not ever open all the way except at full throttle? If so, I might be inclined to get a controller instead of tying them off.

Open 100% in sport mode after cold start and idle settling. Then you can remove a fuse to leave them that way. Fuse is in the trunk on the right side behind a panel sitting behind a small cargo net. Number 203.

[mjr24]

Originally Posted by __AD__

Open 100% in sport mode after cold start and idle settling. Then you can remove a fuse to leave them that way. Fuse is in the trunk on the right side behind a panel sitting behind a small cargo net. Number 203.

Thanks, bud!

[ctelimad]

Originally Posted by mjr24

Thanks, bud!

It is 203 (passenger side valve) and 206 (driver side valve)
So you have to pull both otherwise u will have only one open all the time

[M8Bimmer]

I bought the Dinan flap opener/closer unit. I like it. Then you some quiet when wanted or needed.

[f8ighym3]

Originally Posted by __AD__

Open 100% in sport mode after cold start and idle settling. Then you can remove a fuse to leave them that way. Fuse is in the trunk on the right side behind a panel sitting behind a small cargo net. Number 203.

I was told that the flaps ONLY open 100% in sport mode during a cold start but after the idle settles, they close a bit. If this's the case, is it best to remove the fuses during a cold start (before the idle settles) to keep them open 100%? Can anyone clarify?

[mjr24]

Originally Posted by f8ighym3

I was told that the flaps ONLY open 100% in sport mode during a cold start but after the idle settles, they close a bit. If this's the case, is it best to remove the fuses during a cold start (before the idle settles) to keep them open 100%? Can anyone clarify?

Yeah, I have heard similar things......curious as to what the truth is.

[__AD__]

On my m850i at least, they’re closed on cold start and then fully open once idle settles. That’s when you pull the fuse. You can watch the valve after you start the car and see it visually open/close.

[danibear]

Originally Posted by __AD__

On my m850i at least, they’re closed on cold start and then fully open once idle settles. That’s when you pull the fuse. You can watch the valve after you start the car and see it visually open/close.

The way you describes is weird like car tries to muffle itself.

I used to experience the other way. OK, I do not have a 8 physically in my hands at this moment, but will be.

May be market location regulations matter? I am in southern US.

[yugrac]

Originally Posted by __AD__

On my m850i at least, they’re closed on cold start and then fully open once idle settles. That’s when you pull the fuse. You can watch the valve after you start the car and see it visually open/close.

+1

[__AD__]

Originally Posted by ctelimad

It is 203 (passenger side valve) and 206 (driver side valve)
So you have to pull both otherwise u will have only one open all the time

Correct! Looks like one fuse for N63 and two fuses for S63.

[__AD__]

Originally Posted by danibear

The way you describes is weird like car tries to muffle itself.

I used to experience the other way. OK, I do not have a 8 physically in my hands at this moment, but will be.

May be market location regulations matter? I am in southern US.

They’re muffling the cold start so you don’t scare little kids and small dogs.

[danibear]

Originally Posted by __AD__

They’re muffling the cold start so you don’t scare little kids and small dogs.

Oh I see……. In the vast southern land, my neighbors did not complain…. For now……

Thanks for informing. So many subtle differences each car has. Very interesting, like reading different books.

[Humy]

So you guys are pulling these fuses while the loud cold start is happening for the 1st 30 seconds of starting the car in sport plus? I never pulled a fuse while car was running

[Johnny Boost]

I used the bimmerlink app to open the flaps then pulled the fuse. No issues or errors from doing it while the car was running.

[__AD__]

Originally Posted by Humy

So you guys are pulling these fuses while the loud cold start is happening for the 1st 30 seconds of starting the car in sport plus? I never pulled a fuse while car was running

Wait until the idle calms down and put it in sport plus. You’ll hear the flaps open (check visually) then pull the fuse. It’s only 7.5a so not much current running through it.

[yugrac]

Originally Posted by __AD__

It’s only 7.5a so not much current running through it.

Actually, there is no current draw when the valve is either fully open or fully closed, but only during the actual opening or closing.

[mikerx5]

Is there a difference in ing the fuse permanently vs just starting in sport individual before turning the vehicle on? I do like the louder exhaust so typically hitting the sport button and then hitting the button does it for me - is it louder otherwise with the fuses pulled?

I love this forum!

[__AD__]

Originally Posted by mikerx5

Is there a difference in ing the fuse permanently vs just starting in sport individual before turning the vehicle on? I do like the louder exhaust so typically hitting the sport button and then hitting the button does it for me - is it louder otherwise with the fuses pulled?

I love this forum!

I believe the flaps close when you shut the car off. The starts are a lot louder with the fuse pulled because the flaps are always open instead of opening shortly after starting.

[Justao]

Originally Posted by mikerx5

Is there a difference in ing the fuse permanently vs just starting in sport individual before turning the vehicle on? I do like the louder exhaust so typically hitting the sport button and then hitting the button does it for me - is it louder otherwise with the fuses pulled?

I love this forum!

If you pull the fuses the flaps will stay always open even in comfort mode! Otherwise the flaps stay open only in sport+ and close in comfort

[mikerx5]

Originally Posted by Justao

If you pull the fuses the flaps will stay always open even in comfort mode! Otherwise the flaps stay open only in sport+ and close in comfort

Got it! So effectively its the same thing as starting in sport mode but allows same exhaust note regardless of setting - thx

[Humy]

I got out car and noticed flaps were open, so pulled the fuses based on this online diagram. Looking forward to next cold start. I only saw flaps on the outer pipes