I recommend to use a mini ratcheting tool that you can attach a torx bit to

Yes on my channel I have a video where I placed a gopro on the rear bumper and drove around in the different drive modes. If you do place an h pipe I'd place it closer to mufflers like the stock PE has it. Although typically h pipes are placed closer to the engine, I'd take after how Mercedes designed it for the PE and place it in the same spot.

@@chrisc8089 would you recommend two h pipes? similar to logos engineerings exhaust?

@Boosted.450 probably not, the first h- pipe they added was oversized compared to the second one. If you can have one made like that I'd say go for it. Iirc they added it oversized to help deepen the sound

@@chrisc8089 sounds good i’ll try one H pipe first and if i still think it could sound better maybe i’ll add a second one, just want to smoothen the rasp out as much as i can with the catless. Only reason for catless is I like the super loud noise compared to catted.

@@chrisc8089 also where did you get your H pipe and X pipe from?

No these dp's have a 200 cell cat on them

Sounds more like a malfunctioning exhaust valve, if you have the performance exhaust? If so it may only come up on a scan using a professional scanner that can read Mercedes specific faults

@@chrisc8089 No performance exhaust , the ecu controls my pops. No dtc's in ecu or tcu. I feel lile its the acuators

Cracked crankcase breather hose under intake plenum, full power restored

Car wont pop or backfire if theres a vacuum leak no matter how minor

@@c43sedan that's good to know! Thanks for the update I'm sure it'll help someone

The orange piece, which is the flexible diaphragm/valve that breaks down over time. It should be completely whole and no part of it missing (as in the video). Also the o-ring on the connector I removed should be intact and not torn. The hose should also be in good condition too, so that there is no vacuum leak. There's most likely nothing wrong with the hose but always good to take a quick look.

@@chrisc8089 thank you because i notice after a couple hard launches the car feels like it has no boost. And the exhaust becomes REALLY loud at low rpms when there’s no boost.

@Boosted.450 although you should check this vacuum pump valve since they don't seem to last long... it definitely sounds like you have a different problem if the exhaust became louder. Without hearing or seeing the car, I'd guess possibly an exhaust leak, boost leak or something else ( hopefully not worse). From what I've seen other people mention, a common area for boost leak is the connection from the top of the intercooler to intake manifold.

@@chrisc8089 thanks i’ll give it a look

Making the exhaust a true dual will help change the overall tone for the better. Which mufflers are you using on yours? Catless downpipes will greatly contribute to the rasp of the sound, that is the number one factor. Any high-flow catted downpipe would be much better. Curious to know which mufflers you went with though. I have the stock C450 mufflers except they've been modified. I had the casings opened up to make the piping inside exit straight out (so now a straight pipe). There is also a helmholtz chamber in the OEM mufflers which is what cancels drone, I kept that section intact. I had the same shop cut out the entire middle pipe, and make it a true dual exhaust using 2.25" pipes to the muffler. 2.5" would have been better though. I do still have a resonator on mine,. I am using the C43 performance exhaust resonator. Although without the resonator I am sure it would sound practically the same since this particular resonator does very little to dampen sound. Lastly I have an x-pipe placed where the h-pipe is on the C43 performance exhaust. I may experiment with swapping for an h-pipe instead soon.

@@chrisc8089 I am using Valvetronic designs universal valved muffler kit. Total cost with install was only $700 and a couple hours of my time to setup the valves. My only issue is I went to two exhaust shops and they both said they can’t do true dual exhaust. The resonator that i put on took away the rasp but made the entire car burbles, sound, upshift fart about 50% quieter. Was thinking about buying some 2.5 inch stainless steel piping and having a friend custom weld a true dual with no x or h pipe.

@@Boosted.450 ahh I see, you might need to find a different exhaust shop then. Unless your friend could also put some bends in the piping on its way back to the mufflers, then I would recommend finding a different shop. Some bends in the piping help break up the sound waves and reduce rasp further. Are you by chance in norcal area? I can recommend the shop I went to For pics of my exhaust setup check post #24 on this thread from mbworld forums, only difference is I had the C63s mufflers installed in this pic instead of my modified C450 mufflers. mbworld.org/forums/c450-c43-amg/792098-bmw-mod-opened-up-my-c43-mufflers-semi-straight-pipe-w-pics-armytrix-sound.html#post8355860 When I had the C63s mufflers on, not only did it drone a lot but it also reduced the sound of burbles almost completely. I could only hear the high RPM burbles. Those mufflers don't pair well to the exhaust generated from our motors.

@@chrisc8089 I’m in SoCal unfortunately, but i’ll take the shops name! Also how much did it cost to complete just the custom midpipe, just wondering so I can offer another shop that figure if I find one!

@@Boosted.450 The shop is called Muffler Tech in Sacramento. Awesome shop. If I remember correctly the mid-pipe job was $500. I just brought the PE resonator with me and told them what I wanted, a dual middle pipe with the resonator and an x-pipe. They originally estimated about $400 but it ended up taking longer than expected. I had a friend who did the dual exhaust middle pipe mod at a different shop for $300.. He had them do dual 2.5" piping with an x-pipe placed where I put my resonator. Took less time to get the welds done since less parts to weld together. Every shop is different for sure, I was quoted prices anywhere from $400 - 1000. Some shops suck, some want to upcharge when they hear "it's a mercedes". I suppose it just takes time finding the right honest shop who does custom exhausts very often.

Bad fitment, no way to make the passenger side fit on the C450 properly without removing the heatshield guarding the front differential. I did remove it in order to bend it to shape to make clearance. I was extremely careful with shaping it (which is hard to do since it is thick) only to find out a part of the driveshaft/bolts was hitting the heatshield while rotating. I bought a new heat shield and said fuck it, returned to stock. These were installed on a C43 no problem, and I sold them to another guy who has a C43 with no problem. Supposedly, LEM offers the "stealth" series 250 cell downpipes which has an identical shape/design to the stock cats and should have no fitment issues. But I am not going to even entertain trying unless another person tries first, I wasted more time and money on trying these dp's than I wanted to especially when their site claimed it fit. Now they updated the site to say for some models it will require modification.

So these are the LEM monster downpipes, i bought some on marketplace and haven’t installed yet. Seller claims they fit c43’s but were never installed and i bought them brand new. I checked on logos site and see that they match the glc43 monster downpipe pictures. Will they fit my c43?? Lowkey scared they won’t fit

At first what you described sounds just like the same problem my car had. But I'm unsure what you mean about it would make it so that you cannot launch the car again. However, the second half of what you mentioned sounds like a different issue altogether. It could be several things causing that, but I would've thought that the car would be throwing a code in that situation. If the diverter valves were commanded open it would dump any boost the car would be trying to make, and your car would feel like it's only making about 200 hp. The car can do other things to prevent boost from building, such as limiting throttle to around 30% where it would seem to take forever to reach redline. If you have faulty pressure sensors on the intakes, faulty boost sensor, faulty wastegate solenoid amongst other things... it could cause no/low or sporadic boost. I guess in your case it's still a good idea to check the vacuum valve, but I suspect something else is going on for sure. Like the C450, the C400 didn't come with ability to build boost when trying to brake boost launch it. Most early tunes didn't add this ability, AMR added this ability first then I think one of the EC locations did next. But I'm sure you'd know if your tune has that capability programed into it. The first tune I put on my C450 didn't.

@@chrisc8089Hey, thank u for the response. I have replaced the vacuum pump valves, but no difference. I am starting to think it might be one of the sensors as you said. My wastegate actuator, like the rod itself, is vibrating like crazy on the drivers side. Do you think that has anything to do with it? I have no codes at all and the boost still comes back every now and then. My throttle isn’t being limited as i’ve been drifting and stuff, hitting redline pretty easily but it just has NO boost smh. My tune doesn’t have the ability to launch either. I don’t really mind that I just want to be faster than 200something HP.

@dhillon21 yeah it's worth looking into those wastegates and possibly replace them. Some people get the rattle with no issues, but I've also seen some people mention theirs needed replacing. However, also look into the wastegate solenoid it's another part that can have issues and it's not uncommon. The best thing is to figure out a way to log your data, even if using some free app on the android/Apple market. Try to log data because without that, it's really hard to tell.

@@dhillon21 Hey did you ever figure out the issue? I am having the same issue ;(

Yes, you're referring to the boost gauge of the AMG menu? If so, from what I guess the boost data isn't being transmitted to or used by the C450 gauge cluster. You'd think this could be fixed with proper programming but it seems that either it's not possible or that nobody has done it. Perhaps it's too much work to make happen from a programming perspective. People are activating the menu on the C450 which doesn't come with it from the factory, and the boost reference gauge just doesn't work. I had mine activated a couple years ago and the boost gauge doesn't even appear on the menu, only the oil temps. So in some cars where boost gauge option isn't working some of the guys selling activations are leaving that out instead of enabling it. I've heard a couple of times people saying that the gauge clusters are very slightly different after 2016 for the C43, and that there's one extra wire in the harness. They seem to indicate that's the reason why but I've not seen any proof to that, and to me it's all hearsay until someone actually proves it.

The orange valve likely tore to pieces over time, and the vacuum pump would've chopped it further. But I wouldn't worry about that. I did see the pumps have a metal screen where oil flows but i wouldn't suspect the tiny pieces to clog it. On mine there was no clogging. The orange piece is fragile it seems.. I'm sure the pump would have noticeable issues if that were the case. You aren't the first person to report the orange valve completely missing, and in no case have I seen it be an issue other low boost

@@chrisc8089 quick update, I got the replacement valve and a cheap endoscope from Amazon and of course I found the the black plastic cap and what was left of the rubber valve inside the pump, fished them out with a paper clip. Car is shifting faster now, everything seems to be working better, even the breaks.

@calikickzt that's great to hear!

The casing of the original sport mufflers were cut open on the top, and the internal pipe routing was rerouted to exit straight out as opposed to circling around inside before exiting the back. Inside the muffler there's a helmholtz chamber to cancel drone and I left that part alone. So it's like a straight pipe with no drone. But the pipe routing in a circle with baffles was killing the tone and restricting the flow. This is a mod we documented on the mbworld forum as well, with pictures and everything. You can find it searching for the thread title called "BMW Mod"

@@chrisc8089 Ahh, would it sound like that for a facelift C43? I got a 2020 and I don’t want it to get raspy

@xcodstur926 yes it'll sound exactly the same. If you do the mod it would be a good time to have the exhaust shop convert the middle pipe to a dual pipe. The sport exhaust uses a Y-pipe instead of a true dual piping like the Performance Exhaust. That's what I did on mine, and used an x pipe instead of h-pipe like the PE, but an h pipe would be great too

Boost not engaging at all? Have you had the ECU scanned to see what underlying codes might be set? It could be many things, including this problem especially if the vacuum lines clogged with oil. But I have a feeling it's something else Do you have aftermarket intakes? I've ran across a problem once where my throttle was limited to 30% and the diverter valves were commanded open, making the car feel extremely slow no boost. Also RPM was slow to climb.. except that I also had CEL in this case.

@@chrisc8089 hey thanks for the reply back boss. So it SOMETIMES works great half the time it won’t give me boost at all ! Also it is making a rattling noise couple of friends said it might be my waste gates.. I also have stock intakes. I already ordered this part online and will try this first before taking it to service

@@chrisc8089 I took out the valve and it has oil around it. Not sure if that’s a indication that it’s bad

@amgc4392 oil around it is normal, and as long as the round orange valve itself is intact, no pieces missing then it's good. A lot of guys have wastegate rattle problems on this platform, but I've not seen them report having boost issues. The bypass flap part of the wastegate that's in the exhaust stream is typically where that rattle comes from. It's difficult to diagnose these types of issues without scanning the ECU or looking at the live data. Is the rattle noise present all the time or only during the lack of boost? Any other symptoms you've noticed, or specific driving conditions where the problem occurs, or is it just random?

@@chrisc8089 understood I will do it tonight and check.. And it’s all the time! I noticed its gets really loud when I’m sports +…. but on comfort mode it is a light mild noise.

Sounds like the same problem, only one way to find out! Check this valve inside the connector, and luckily it's cheap and quick to replace. It's a good start to diagnosing your issue, which I'm guessing is the same problem

Sounds identical to the issues I had, but it could be a number of things. Luckily, It's fairly quick to pull the connector out and check for the orange valve, and if it's missing pieces or missing altogether. I think checking this valve should be the first thing anyone should check when having these symptoms.

You're welcome, keep us updated on how it turns out!

Try eBay www.ebay.com/itm/115045707705?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=WNmZrqelQ1K&sssrc=4429486&ssuid=zhNR6hqWTti&var=&widget_ver=artemis&media=COPY

I bought the car with 32k miles after someone leased it for 3 years, tuned it at 34k miles. Never did any 0-60 mph testing until around 36k miles which is when I noticed something wasn't right. Around this time I also installed a boost gauge and did some basic logging of boost, afr and other things. The valve could've been bad even before I bought the car and I just never noticed. No code.. ECU doesn't even monitor the vacuum on this line. Basic troubleshooting on and off over some months. Checked everything I could think of, but the last thing I considered to be a problem was vacuum pump. Brakes were working fine and so I prioritized troubleshooting other areas first. One day I also had a friend come over with the same car and tune, we did some back to back testing and monitoring of boost for the sake of comparison. This is my first Mercedes and I was also still a bit unfamiliar with this platform.

​@@chrisc8089 - It could have been a manufacturing defect. When you make tens of thousands of parts there will be bad ones although low numbers. The tune does add more stress on internals and components. Is the tune a JB4? Would be great if you could update down the road. I'm looking at buying one in the next week. Thanks

@The_McD I went with AMR for tuning. Started with ECU then got the TCU done a year later. My 0-60 times went anywhere from 4.5s - 4.9s before I replaced the vacuum valve. Which is practically stock times, but from a roll the car felt very noticeably faster. It was only trying to brake boost launch the car where it was noticeable that my 0-60 times were terrible. After fixing the valve I ran a 3.70s, and a couple 3.76s 0-60 dragy runs. For reference this is a C450 so it has the 7 speed transmission, and also the tune map is for 91 octane gasoline.

It sounds like the exact same problem, and if so then it's an easy and cheap fix. Search on Amazon or eBay for "m276 vacuum pump repair" and you'll find this connector with a new rubber orange valve for around $30-40. However the same exact part seems to be sold under "Ford Ecoboost vacuum pump repair". I bought one and test fitted it to my spare pump and it was the same but only $10

@@chrisc8089 ok I just ordered it on ebay, thx for making this vid I've been chasing this boost leak problem for awhile looking at every coupler etc not understanding why boost jumps allot and can't wait to get it fixed 👍

@@vladt6038 yw, I had spent months trying to figure out why my car was not getting full boost and bad times. I checked every other thing I can think of and replaced several parts. I finally narrowed down to the vacuum pump. But the whole time I didn't really suspect the pump, I knew the pump itself should've been OK since my brakes are still working the same. And of course, it turned out to be this one way valve on the vacuum pump for the turbo wastegates.

@@chrisc8089 thanks allot man this was is an insane diagnosis that you found this 😁 I actually just managed to change mine today and when I took it out the orange rubber inside was actually hanging out inside the pump and I had to pull it out and it was all hard plastic disintegrating. Nevertheless put the new one in and now my car boosts like crazy.

@vladt6038 that's great to hear!

It may get sucked into the pump and will likely just become chopped/grinded up inside of it. I believe that's what's happening anyway as it disintegrates. There's a screen on the pump for oil to flow, the screen can become clogged but it's not likely happening or an issue. Mine had none of the diaphragm clogging it, but I did see a very thin amount of old oil that was hardened slightly clogging it. If yours is stuck, I'd try to get a fine picking tool like at autozone or pep boys and try to grab it out

Did switching to pe resonator make a difrence? Or mostly muffler modification?

It did make a difference in making the tone deeper and very slightly louder. Some of the softer low rpm burbles that I couldn't hear before had become noticeable after the mod. One of the best things you could do besides the muffler mod, is to convert the middle pipefrom a Y-pipe to a true dual pipe with an X or H crossover. That will change the way it sounds, and change the tone a bit too.

@@123kiashi the PE resonator didn't do too much at all, but I was planning to add downpipes and wanted to keep a resonator of some kind.

Thanks for reply chrisc! Next week i am doing custom muffler mode. We will disconect ypipe with mufflers, and they will make new ypipe and new mufflers. Custom Muffler will have hemholts chamber as the stock one and a straight through pipe and not 360pipe with small holes(pipe will belittle bigger than in stock muffler). So i keep stock muffler stock if i wish to switch and get a new one that will be simmilar to your modified one. Hopefully i get more sound and no drone 🙂 thanks again

Yes, this is the only valve for the pump. The other end of the hose connected to the vacuum pump is connected to the "pressure transducer," aka the wastegate solenoid valve. If fixing this vacuum pump valve doesn't completely resolve your problem, it may possibly be that solenoid isn't operating correctly anymore. Or something else completely such as a boost leak etc. When I first discovered my vacuum pump valve was damaged, it also was not a complete disc anymore. It was disintegrated to about less than half the original size

@@chrisc8089 Awesome man, I definitely appreciate you. This is the only information I have seen online regarding this. My valve will be here tomorrow and I will run some more logs.

No some boost can still be built up even if the diaphragm valve was completely missing. If you are experiencing no boost do you also have an error code/CEL thrown by the ECU?

The one I purchased was shipped out of China This is the one I bought from my video, that I compared to OEM valve: www.ebay.com/itm/234551686530?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=1bPiXzwbTRC&sssrc=2349624&ssuid=zhNR6hqWTti&var=&widget_ver=artemis&media=COPY You can find this one from a US reseller, searching for the same Ford ecoboost valve.

@@chrisc8089 thanks man. i ended up finding one on amazon. they mentioned it from ukraine & good quality lol. Cant wait to try it on my tuned c450

@@greyeuro yw! It definitely made a big difference for me and many others who had this problem

@@chrisc8089 Just did this to mine. I had to wait about a month for the part to arrive from Ukraine but well worth it. Ran an 11.46 dragy run before on my c450. Now the car feels faster. Thanks again for video!

@greyeuro nice, you're welcome bro! I saw your Dragy video on the FB group. That's a solid run! Good stuff

2nd gear felt normal when doing a run from a dig. When I was just cruising along in traffic there's some initial lag going full throttle, but it was barely noticeable. I didn't even realize it until fixing it. Partial throttle boost while in traffic was lower by about 1-2 psi. These were the typical symptoms in any gear. Not sure about the 9th gear at 150 km/h, I don't typically drive it that fast. Btw I have the 7 speed in mine (2016 C450). From my experience with this issue.. Generally, once the car is already revving higher, then the damaged vacuum valve won't really be much of an issue since there is enough vacuum generated by the pump for the wastegates to still operate properly. The vacuum pump is connected to the end of the camshaft and rotates with the motor. The valve helps to hold vacuum in the hoses going to the pressure transducer which operates the wastegate. The wastegate is actuated by the vacuum. It was mostly noticeable at low speed/RPM and when trying to brake boost launch the lack of vacuum threw things off for the entire first gear - causing boost fluctuations and boost never exceeded 10 psi.

@@chrisc8089 Thank you for information, i order new pump and i hope there will be some diference... maybe i feel most diference in 2nd gear because my c43 is stage3 tuned 520hp 780nm... and mercedes servis told me that my pump do not make any presure... sory for my bad englis haha

@Marcel levanic you're welcome. Also keep in mind that the "pressure transducer" is another fairly common part that fails in our cars, so that might be the next part to check if the vacuum pump doesn't fix it. The dealerships only sell whole vacuum pumps and not the valve unfortunately. But at least we can get it online. What are all of the mods you've done to yours? I'm very curious 🙂

@@chrisc8089 Presure transducer is okay i check it last week, so is almost 99% that is vacum pump. Remap, downpipe, resdelete, mst intake, weistec hybrid turbo... and is much faster then stage1 tuned f82 m4... Now i have to start the visual rework haha, because i want it look more agressive

@Marcel levanic nice! If you have an Instagram of your car I'd love to check it out. As part of the turbo upgrade, Did you also upgrade fuel pump by chance?

Yes that's exactly what was happening. Immediately after a brake boosted launch the boost would drop, then jump up and down never exceeding 10 psi. Once it shifted to second the boost was back to the normal and expected range

@@chrisc8089 did you ever get it fixed ? I wondering what I have to fix. Boost pressure sensor or vacuum pump ?

@TRiniBAD_AMG yes in this video is the part to replace. The diaphragm to the wastage vacuum was disintegrated, there was almost nothing left of it. So the weak vacuum was causing the low boost. You may just need the diaphragm/fitting replaced. You can find these on ebay, if you search for w205 Mercedes vacuum repair www.ebay.com/itm/115045707705?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=WNmZrqelQ1K&sssrc=2349624&ssuid=zhNR6hqWTti&var=&widget_ver=artemis&media=COPY

@@trinibad_amgc43 I already repaired it before making the video, so my valve in the video is perfectly normal since it was already replaced to fix the issue

I actually removed them shortly after install, fitment on the C450 was too annoying but I'm looking forward to buying their latest downpipes. Which are the 250 cell stealth series downpipes. Those are supposed to fit all models good without modification. Sorry I didn't take any drive by videos before removing them, but they did smell a bit more on startup. I didn't notice any smell driving around at operating temperatures. I imagine they're slightly more smelly at all times

Any updates with the stealth series?

quick question, why was the install annoying?

This is the LEM air intakes, which I then wrapped in gold reflective heat wrap. They also have a new version of an intake releasing soon, which upgrades the inlet of the OEM intakes. Both are solid options

I have a muffler delete and mine sounds really similar to yours

@@drivescene6747 thank you! These are my favorite exhaust tips/diffuser for these cars. I love my exhaust setup, I may consider getting downpipes again in the future.

@@chrisc8089 no prob man. Please make more videos lol I’m subscribed

I got this one on aliexpress, however there is a different and very reliable source to get aftermarket parts from China. Not to mention the solid customer service. If you're on the Facebook c43 group moderated by AMR, there's a seller by the name of Bahua Liu. If you message him about any part he can get it for you for a great price. I've bought a few things from him and many people have gotten this diffuser from him as well.

I do have a resonator, specifically one from the C43 AMG Performance Exhaust. So my midpipe looks just like the performance exhaust midpipe, except where there is an H crossover, I placed an X crossover. You could get away without the resonator and I'm sure it'll still sound good with the modified muffler. The muffler has no fiberglass packing anymore as it was no longer needed anyway. The helmholtz chamber in the muffler has zero fiberglass and was left alone. Only the other half of the piping inside the muffler was modified, which is where it circled around and was expanding exhaust into the fiberglass packing. That part was cut out and made into a straight pipe to the outlet of the muffler.

Got it thanks! so both mufflers straight piped inside and all insulation out. I Was worried about drone and was only going to do the res delete with x pipe and dual pipes going to both each muffler at first but I will mod the mufflers as well at the same time. you have no drone and exhaust definitely sounds nicer with these modifications so win win and cheaper too!

I used a GoPro hero 8 black with the official GoPro suction cup mount 👌

Yes no drone. The exhaust is a bit louder in comfort mode so there's a slightly noticeable increase to lower frequency sound inside the cabin. But there's no annoying drone - this is the perfect setup imo. I'm still waiting to see more feedback from people with the LEM preforms exhaust replica though, they look good but I'm sure they drone with valves open. I'm also planning to install catted downpipes as well and I'll see how it affects everything. I previously installed C63s PE mufflers on this same middle pipe setup and it droned so badly I couldn't stand it. Cruising in the city or highway, it was so loud and rattling the cupholder. Had to keep the radio volume higher to hear it, very annoying lol.

just put the PE midpipe on my car and connected the stock sport mufflers. hopefully whenever i do this muffler hack. it will sound just like the PE. right now i’m very close, i can tell that i just need to open up the muffler a bit to be able to fully hear its soul

@@realcrimecams it will have a similar but different sound, it will sound great!

@@chrisc8089 you rang?..LOL. We have V2 completed of our Performance exhaust replica. It has a resonator (we cut open the OEM PE resonator to use as a benchmark) and the drone is comparable to a OEM PE with valves fully open in comfort mode (this is the benchmark we aimed for). send us an email for pics.

@@logosengineeringmotorworks2832 oh really ok, that sounds more like what I'd be interested in. A nice refined tame sound without too much drone , if at all. However I'm happy with my current exhaust, but I'm sure others will be very interested as well. We all want to see more proper drive videos, including WOT and cruising. It's hard to make a decision without hearing it properly with stock downpipes for comparison. I am however still looking to get an intercooler sometime by summer

How are you liking them so far?

@@chrisc8089 no issues thus far.

Thanks, I absolutely love the sound. In my opinion I like it better than aftermarket systems.

Yes the stock Y pipe was removed and thrown away. I had the shop make a custom dual middle pipe that connects to the stock mufflers (which were cut open and the piping inside modified). I Also have the C43 Performance Exhaust resonator on my midpipe and an x-pipe. I've got a few other videos I've uploaded you can check out as well. For details on the configuration and more sound clips, please see the forum post on the muffler mod here: mbworld.org/forums/c450-c43-amg/792098-bmw-mod-opened-up-my-c43-mufflers-semi-straight-pipe-w-pics.html My screen name on the forum is BayAreaAMG. You can check out my pictures and progress there .

The C450 never had the option of the PE system like the C43's, unfortunately. I have the standard "AMG Sport mufflers" , which are what you get when you don't have the optional PE exhaust system. However what I did was add a resonator from the C43 PE system onto a custom fabricated dual midpipe (the factory midpipe was a large Y-pipe configuration). After the resonator I added an X-pipe. So I still have the regular mufflers from the original C450 exhaust, which are the same as what comes installed into the C43 that doesn't have the optional PE. But keep in mind I also had the shop open up the muffler casings, and convert the internal piping of the muffler into a straight pipe. Technically it's a semi-straight pipe, because I still left the helmholtz chamber of the muffler so that I don't have any drone. The piping inside the mufflers were originally circling 360° and expanding into fiberglass which dampens the noise and restricts flow.