M4 Stock Exhaust => M Performance / How Inside Change ?

[danniexi]

Originally Posted by Lifestyler

But IAm 95% Sure there is no damping wool inside.

correct. when i purchased my MPE i took a flashlight to attempt to see what was inside.... basically a hollow muffler with some piping in the middle but no insulation whatsoever.

[Banma]

Hey so can anyone help me with these tips? I just assumed they would be chinese/ebay knock offs, but they might not be... all the ones on ebay have a clamp on the back, these have the same set screw design as the m performance tips on my car (unless those are fake too! &#129315. Who here can help me authenticate these?

Theyre in super bad shape and need to be reconditioned

[Banma]

Finally caught a break in the weather here. Put the sunshine to good use. Step 1 is done.

[aBMWfan]

Originally Posted by Banma

Finally caught a break in the weather here. Put the sunshine to good use. Step 1 is done.

Nice what did you use to clean it? Can’t wait till you get this opened

[aBMWfan]

Originally Posted by Banma

Hey so can anyone help me with these tips? I just assumed they would be chinese/ebay knock offs, but they might not be... all the ones on ebay have a clamp on the back, these have the same set screw design as the m performance tips on my car (unless those are fake too! &#129315. Who here can help me authenticate these?

Theyre in super bad shape and need to be reconditioned

They’re real. I see the screw is there too for that tip make sure all 4 of those.

[Banma]

Originally Posted by aBMWfan

Nice what did you use to clean it? Can’t wait till you get this opened

Fine wire brush attachment for a power drill for the heavy caked on soot. SOS pads for the rest. Weather permitting, I'll make the first cut tomorrow!

[Banma]

Well chaps, there you have it. The inside of the M Performance muffler. Not much to it. I can't really see any way to modify it. Maybe remove or open the short length of pipe that sits between the side of the can and that baffle? Any thoughts?

[Ed_rx7]

Wow..... no damping at all!!!

What effect would you filling it be?... a deeper sound?

[Banma]

Originally Posted by Ed_rx7

Wow..... no damping at all!!!

What effect would you filling it be?... a deeper sound?

I'm sure that wool would just lower the volume... but I have no idea how it would change the tone.

[Banma]

Im wondering if removing this little peice of pipe on both sides will allow the sound to escape more easily, raising the volume a little? That might be my next move

[xelionz]

Hi my MPE has rattles during cold start, anyone here experiencing the same symptoms and if so is there any fix to this?

[Banma]

Oh god, that's awful. Code out the cold start!

[Lifestyler]

Originally Posted by xelionz

Hi my MPE has rattles during cold start, anyone here experiencing the same symptoms and if so is there any fix to this?

Cracked

[CanAutM3]

Originally Posted by Banma

Im wondering if removing this little peice of pipe on both sides will allow the sound to escape more easily, raising the volume a little? That might be my next move

Note that there is not much you can do to change the volume with the valves open, since the exhaust flow bypasses the rear muffler entirely when the valves are open. With the valves open, the rear muffler serves as a Helmholz chamber, so modifying it might change the tone.

[CanAutM3]

Originally Posted by xelionz

Hi my MPE has rattles during cold start, anyone here experiencing the same symptoms and if so is there any fix to this?

Sounds like a cracked MPE . You might also want to check your tips to ensure none of them have become loose.

[danniexi]

Originally Posted by xelionz

Hi my MPE has rattles during cold start, anyone here experiencing the same symptoms and if so is there any fix to this?

check for cracks. if there are no cracks, check the exhaust valves. i had a similar rattle and it turned out to be the exhaust valves (which i got replaced under warranty.

[xelionz]

Originally Posted by danniexi

check for cracks. if there are no cracks, check the exhaust valves. i had a similar rattle and it turned out to be the exhaust valves (which i got replaced under warranty.

The exhaust valves symptoms causes the flaps to be closed permanently?

[danniexi]

Originally Posted by xelionz

The exhaust valves symptoms causes the flaps to be closed permanently?

no, they were moving/operating as intended, but for some reason they werent seating properly (especially with valves closed) so they were rattling. not 100% sure, but whatever the case was, they were the culprit and were replaced accordingly.

[xelionz]

Originally Posted by danniexi

no, they were moving/operating as intended, but for some reason they werent seating properly (especially with valves closed) so they were rattling. not 100% sure, but whatever the case was, they were the culprit and were replaced accordingly.

Thanks for the information, will definitely highlight this to the dealer.

[StackedM2C]

has anyone here completed the oem exhaust mod ? i am trying to have it done myself but unsure if i want to block off all the perforation holes, please let me know. thanks!!

[WarMachineM3]

Originally Posted by Banma

The donor is here, an ugly cadaver but thats ok. We're going to open it up, poke around inside for science, then put it all back together and try to bring it back to life. I feel a bit like Dr Frankenstein

Would still happen to have the carbon tips?

[WarMachineM3]

Originally Posted by whoop_ass

Some progress so far and some welding porn

no idea what it will sound like but we will pack it tight to keep tone down with the valves closed.

Do you still have this muffler?