[warrenw]

Originally Posted by Peterglen

I never installed my sound kit. I guess I probably should!

It's worth it. Valves open in comfort mode is a great "street" sound.

[quenotte]

Originally Posted by Westerwälder

It is an official statement by munich which has been sent to all dealers. Every modification on the complete exhaust system will be flagged in their system and MAY result in the denial of an exhaust related fault (such as turbo and so on...). Reason was the potentially missing back pressure of the exhaust and therefore a faulty operating OPF, for example.

Do you have the official note/statement from BMW?

[lnsaneM]

Is the full ak exhaust for the og m2 the same for m2c as well?

[vale007]

Originally Posted by kart driver

I was in a position to buy a better exhaust to make the M2C with OPF filters sound a bit better than a vacuum cleaner.


Having an extremely positive experience with a slip-on from Akra on a 911 GT3, I thought that I will go the same route with the M2C.


But just before placing an order for the Akra, I just asked to hear it in person on a friend’s car.
I know the sound preference is always subjective, but I didn’t like the sound of the Akra slip-on on the M2C at all! It sounded like a cheap exhaust to my ears, producing an irritating noise.


I am a bit frustrated as:
- I was just 100% confident that the Akra will sound the best and I expected to resolve the issue asap and enjoy a beautiful sound of Akra in the nearest week.
- I don’t like the current sound of the OEM exhaust with this weird OPF thing as the engine makes just no noise at all


The second option for me would be MPE or Remus given to all the videos, which I watched on Youtube. But given bad experience with Akra on a friend’s M2C I am afraid to order anything without hearing it in person.

[kart driver]

Originally Posted by vale007

Attachment 2412528

I have no idea of how it sounds on the M2C but all supersprint exhausts, which I heard in the past on BMWs sound less beautiful than Akra and M Perfomance.

[Tupps11]

Originally Posted by VisualEcho

You bought the wrong car to have a good sounding exhaust.

The guys that think they have made it sound good have only made it loud enough that they don't care anymore.

Spot on.

This car won't ever sound good. Just loud. Sadly, I've come to terms with it and started the process to make it loud.

[kart driver]

Had a chance to hear M2C with Akrapovic rear section + Akra midpipe today.

It sounds really different compared to Akrapovic rear section only.

Everyone, who is buying Akra rear section only, should also add proper Midpipe (Akra or alternative like AA eual length)!



As a conclusion, which I also found proof from other knowledgeable people: the problem of S55 poor sound is resolved with adding a proper midpipe in the first place.

Even if you leave the OEM rear section and just pair it with AA equal length midpipe dramatically changes the sound for better.

[RockStone]

Originally Posted by kart driver

No-no-no!

I am:
- willing to keep the BMW WARRANTY, so only slip-on solution is considered, no coding!
- considering exhaust options, which are sold in Europe
- willing to have a civilized sound, not a crazy screaming one

In my opinion, if you want to stay under the warranty and add some slight beefy sound to your M2C's, go through the original M-Performance exhaust. I can bet that its TUV approved

[kart driver]

Originally Posted by RockStone

In my opinion, if you want to stay under the warranty and add some slight beefy sound to your M2C's, go through the original M-Performance exhaust. I can bet that its TUV approved

That was my initial idea ))
Things change with time ))

Since AK motion eliminates completely the issue of OPF delete and no coding is needed then I can go this route.

[RockStone]

Originally Posted by kart driver

That was my initial idea ))
Things change with time ))

Since AK motion eliminates completely the issue of OPF delete and no coding is needed then I can go this route.

Waiting then when you will sort it out, cause need to kill a unicorn to make s55 sound better )

[LakiTopalovich]

Question for those with Akrapovic evolution (link pipe) / sound kit: When you close the flaps with provided remote controller are they permanently closed or they just revert to stock (active) mode? In other words, can I keep flaps in active mode after installing evolution pipe with sound kit?

[2020M2Competition]

Originally Posted by LakiTopalovich

Question for those with Akrapovic evolution (link pipe) / sound kit: When you close the flaps with provided remote controller are they permanently closed or they just revert to stock (active) mode? In other words, can I keep flaps in active mode after installing evolution pipe with sound kit?

The remote switches between stock and always open

A quote from forum member MR in another thread

" The remote doesn't switch between OPEN and CLOSED! Guys, please stop thinking that. It is NOT true. The remote on an Akrapovic exhaust switches between AUTO and OPEN.

AUTO = The normal behavior of the vehicle as BMW developed it and how the stock ECU wants the valves to open and close.

OPEN = Valves always open and the BMW behavior is being overwritten.

In Efficient mode, the switching means that you think you switch between open and close, but you are NOT! BMW developed the valve behavior that the valves stay closed in Efficient mode and it is only open when you go full on WOT on the throttle. Try it and you will hear the exhaust valves open at around 4K rpm. The remote overwrites this and opens the valves always if the remote is RED.

In Sport and Sport+ modes, the switching is nothing other than in Efficient mode!! You are either following the behavior of the BMW ECU valve program or the valves are always open. The reason you hear not much difference is that you might not have removed the interior false exhaust note called ASD or you are not paying attention, because put the valve open, go to manual shifting and give the car some beans... You will hear some decent sound coming from the back, especially around 3K rpm and above.

The automatic valve behavior of the car programmed by BMW is as follows in Sport en Sport+

Depending on the input of your throttle in Sport or Sport+, the car closes the valves at different RPMs ranges or gears. At low input the valves close when you go into 3rd gear, if you give a bit more input it could be 4th gear. There is also an option in which it closes the valves at 4K rpm. If you go full on, it never closes the valves. If you go full on (WOT) on the throttle, then it will open the valves immediately.

You must hear this difference, but it could be if you haven't remove ASD and that you are listening to the interior sound track instead of the real exhaust!! BMW did something really smart with this... In Sport and Sport+ mode, the interior sound from the speakers (the fake exhaust noise) becomes a lot more noticeable over 4K rpm and when the valves are getting closed. They did this making sure the car is not so loud outside, while still giving you the experience inside the interior. The interior sound comes up when the sound outside goes down. Smart idea!

By swapping your exhaust, all goes wrong, because the ASD is not in tune with what you altered underneath the car, therefore remove the ASD and listen to your new exhaust instead! Because I did this as well during the development and testing, Akrapovic decided on improving the valve closing process. We fine tuned the valves closing and opening by installing a sniffer system that looks at the CAN bus inside the car. The system checks when the remote is in AUTO if the BMW valve ECU software is opening or closing the exhaust.

The moment the valve gets closed at like 3rd or 4th gear depending on your throttle input, the Akrapovic control unit alters the speed and way in which the valves closes and therefore making sure the switch between open and close is more gradual and gentle. For people without ASD this is a real benefit, and we engineered it in for you guys to have a better exhaust experience! It is not open/close or loud/silent within one millisecond, but more like cllllloooossseeeee and getting more siillllllleennntttt.... taking a bit of time, allowing the sound track to be more gentle and getting more silent over a few milliseconds.

The Akrapovic Bluetooth remote is only useful if you want to fully open the exhaust at any time or if you want to enjoy the full soundtrack in Efficient mode without all the burbles. I know a far bunch of people enjoy that here! Other than that just leave the remote aside and flick through the modes on the dashboard. If you really want close and open, get an Awron display. It offers OPEN, CLOSE and AUTO via the RES button on your steering wheel.

Any more questions please ask me!

MR "

[LakiTopalovich]

Thank you! That's exactly what I was hoping for

[Driver87]

Good thread. Ordered full Akra for the CS last week.

How much of a PITA is this thing to install? I've got quick jacks, but no help. Just me and the quick jacks!

[msdss]

Originally Posted by Driver87

Good thread. Ordered full Akra for the CS last week.

How much of a PITA is this thing to install? I've got quick jacks, but no help. Just me and the quick jacks!

if you have the full system the pipe is easy to install. it comes with instructions. the crazy bit is the sound kit with all the wiring

[Driver87]

Originally Posted by msdss

if you have the full system the pipe is easy to install. it comes with instructions. the crazy bit is the sound kit with all the wiring

I didn't get it. I figure if I wanted to open it in comfort I'll use BimmerLink. It's always in sport + for me anyway

[msdss]

Originally Posted by Driver87

I didn't get it. I figure if I wanted to open it in comfort I'll use BimmerLink. It's always in sport + for me anyway

weird. it just came with mine. i didn't order it or get the opportunity to opt out of it.. I didn't even know wtf it was when I opened the box. lol

[Driver87]

Originally Posted by msdss

weird. it just came with mine. i didn't order it or get the opportunity to opt out of it.. I didn't even know wtf it was when I opened the box. lol

That's a nice bonus. Purchased my set up through Turner. Sound kit was a add on. I think that would only be useful on a OG unless I'm missing the point of it.

[msdss]

Originally Posted by Driver87

That's a nice bonus. Purchased my set up through Turner. Sound kit was a add on. I think that would only be useful on a OG unless I'm missing the point of it.

as far as I have read, it just gives you more control over the exhaust flaps... but it was a lot of wiring... so maybe it dicks with the active sound stuff also?