When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Updates are coming, I was away on vacation and I still have a few things to put back together, impressive results you got there, cant wait to test mine out.
I'm excited to report today's run #2 and run #3. Less windy today, and results have improved even more.
112km/hr: 66-67 (70mph. Both indicated by speedometer and GPS speeds produce a reading of 66-67db)
120km/hr: 67db
130km/hr: 67x1, 68dbx2
140km/hr: 70db
150km/hr: 70-71db
Exactly! That is amazing on a logarithmic scale. I've been following this thread closely to see the outcome and keep it in my mind when I get my W204.
Thank you for all your work and for sharing it with us here.
Thanks for the kind words. When I have time tomorrow, or this weekend, I'll make a Youtube video indicating exactly what I did to achieve said results :-) If you or others have any suggestions, I'm sure the W204 community as a whole would appreciate it!
Based on C&Ds results and such, my W204 is ALMOST as noisy as an S class at 70mph. I'm certainly thrilled about that :-)
Last edited by superangrypenguin; 03-08-2018 at 08:30 PM.
Ok so finally I got the car together, got my bumper from the body shop and some new headlight sense which I painted black.
As far as the sound proofing that I had added already includes; Dyno mat in these areas : Top of trunk,inside the fender spare wheel area, back seats and some on the front passenger and driver side carpets and each wheel well.
Now all this helped but I wasn't finished, I knew I could get it quieter. So now I had the vibrations figured out, I moved to closed cell foam and MLV mats, i used second skin MLV rolls in the trunk and the rear wheel wells. I then recently found this product called Eco corn foam at home depo which was a third of the cost of the second skin. I got the 75 foot roll and I used maybe 60feet of it inside the fender behind the splash guards and then I covered the splash guard too. I then removed the plastic covers under the floors and covered those aswell.
I then attacked the wind noise in which I followed superangrypengun's tips and put 12mm universal weather stripping all around the doors( front and back) on all 4 doors. The doors now shut like a bank volt, not that they didnt before but it sure made a difference. I didn't bother with the trunk but I added some on the hood gap between the fender and the hood. After words I looked at the seals surrounding the engine and I started inserting some vacuum lines I had laying around to push the seals up ;
Results:
I am amazed on what a difference this all made, using the SPL Sound meter app, I am getting 32-33DB at idle with everything closed and engine running.
70km/h:47DB
100km/:51DB
120km/h:54DB
130km.h:56DB
Now what is amazing, this is with Hakapelita 8's studded winter tires ( brand new) and it was snowing out side so the roads were wet.. I can only imagine the results when I have my summer tires on a dry day, I will post my those results when time comes.
Thanks so much for sharing, and you gave me some ideas I hadn't even thought of (like propping up the engine bay seals). Will give it a shot this weekend, hopefully. I guess I'm not done tinkering with the car
That said, your DB levels seem to be quite different than mine, so that's probably a case of two different apps being used by two different phones, and since it's like 20db different than not only my results but also the ones by C&D, etc, it probably means the results you have require testing info/numbers from other cars, or at the very least, what your car/or a stock W204 would report at for each respective speed and at idle. Do you have the numbers for your vehicle when it was stock?
On another note, I know you and I were looking at adding additional rubber seals for the engine bay (maybe sealing off the sides?) I was wondering if you decided to do that (i don't think you did). I have been studying various designs in this area, and it is worth noting, neither the LS or the S, or the Maybach or the Genesis G90 have that. I wonder if it is indeed due to heat dissipation concerns?
Last edited by superangrypenguin; 03-09-2018 at 07:00 AM.
Thanks so much for sharing, and you gave me some ideas I hadn't even thought of (like propping up the engine bay seals). Will give it a shot this weekend, hopefully. I guess I'm not done tinkering with the car
That said, your DB levels seem to be quite different than mine, so that's probably a case of two different apps being used by two different phones, and since it's like 20db different than not only my results but also the ones by C&D, etc, it probably means the results you have require testing info/numbers from other cars, or at the very least, what your car/or a stock W204 would report at for each respective speed and at idle. Do you have the numbers for your vehicle when it was stock?
On another note, I know you and I were looking at adding additional rubber seals for the engine bay (maybe sealing off the sides?) I was wondering if you decided to do that (i don't think you did). I have been studying various designs in this area, and it is worth noting, neither the LS or the S, or the Maybach or the Genesis G90 have that. I wonder if it is indeed due to heat dissipation concerns?
Yes I did seal the edge of the hood on each side, with the cold temperature outside, I couldn't tell if it made a difference since after an hour drive, the intake box was cool to the touch but that may be because of my heat shield under it. I also sealed the top of the plastic cowl where the twin intake get air, it now seals great with the hood and all the air goes to the intake.
I do find my numbers really low so I will first try a different car and then il download a few more apps to see if there's a difference, which one did you use?
Yes I did seal the edge of the hood on each side, with the cold temperature outside, I couldn't tell if it made a difference since after an hour drive, the intake box was cool to the touch but that may be because of my heat shield under it. I also sealed the top of the plastic cowl where the twin intake get air, it now seals great with the hood and all the air goes to the intake.
I do find my numbers really low so I will first try a different car and then il download a few more apps to see if there's a difference, which one did you use?
Thanks. I just popped my hood and have a ton of stuff to do now. My next target is engine noise, and it appears the C class's engine noise is pretty darn intrusive versus other cars in its class (As per C&D)
To answer your question, I used "sound meter" on my Samsung S7. Sound meter is one of the best rated and most downloaded apps. This video shows the app in question:
SPLmeter gave me useful info, but the db numbers were beyond this world (in the wrong direction) so I gave up on it for the purposes of testing cabin noise.
Thanks. I just popped my hood and have a ton of stuff to do now. My next target is engine noise, and it appears the C class's engine noise is pretty darn intrusive versus other cars in its class (As per C&D)
To answer your question, I used "sound meter" on my Samsung S7. Sound meter is one of the best rated and most downloaded apps. This video shows the app in question: https://www.youtube.com/watch?v=3Nsl_3Tj44M
SPLmeter gave me useful info, but the db numbers were beyond this world (in the wrong direction) so I gave up on it for the purposes of testing cabin noise.
Yes I think I rememeber you having issues with the SPL app, 70db at idle? something crazy like that lool. I will try your app tonight and give some updates.
Yes I think I rememeber you having issues with the SPL app, 70db at idle? something crazy like that lool. I will try your app tonight and give some updates.
Thanks! On a slightly unrelated note, take a look at the W205, here:
I thought our W204s had a lack of insulation, talk about even less on the 205!!
That's embarrassing haha, why did they even bother with that small hood insulator. I dont like where mercedes is going nowadays, there's way to much nissan/renault col lab going on and its hurting Mercedes, starting to look like the early 2000s chrysler merge all over again where they had to step up their game with 2007 + models after ditching chrysler. Chrysler sure loved mercedes since they still use mercedes suspension designs on their challanger and chargers to this day.
That's embarrassing haha, why did they even bother with that small hood insulator. I dont like where mercedes is going nowadays, there's way to much nissan/renault col lab going on and its hurting Mercedes, starting to look like the early 2000s chrysler merge all over again where they had to step up their game with 2007 + models after ditching chrysler. Chrysler sure loved mercedes since they still use mercedes suspension designs on their challanger and chargers to this day.
Agreed. Even after tracking sound levels for the various S classes over the years, no improvement. Merc is becoming too mainstream for my liking. The Maybach S600 is above my paygrade, but I could save for it, I guess. I'm slowly looking at Porsche and some other brands now - I dislike what the German big 3 are doing these days. Everything is getting stupidly cheap, build quality wise!
At idle I am at 30-32DB, this is a new car now and again this is with studded winters, with the winters closed you cant tell it has studded tires till you open the windows and they are loud from the outside. Withe my summer tires I expect at least 2-3DB drop, at least.
At idle I am at 30-32DB, this is a new car now and again this is with studded winters, with the winters closed you cant tell it has studded tires till you open the windows and they are loud from the outside. Withe my summer tires I expect at least 2-3DB drop, at least.
Thanks! It appears that at every DB that you recorded, your numbers and mine are off by, say 10db, which is a lot. Now that said, given the fact you've done more insulating than I have, it is very feasible that your @ speed sound levels may be less than mine, (I was thinking just now). That said though, there shouldn't be that dramatic of a difference at idle, mainly because our respective engines aren't under any load, so given that, I think we have to take our numbers at face value, because there is no explanation for the large difference, other than perhaps a different phone/microphone within said phone. If it's possible, I think it would be super useful, if you can, to post measurements on a stock 204 using your phone. I'm genuinely curious what you get there as well.
xsever mentioned upthread he/she would be posting his/her numbers for a CLK (IIRC). I'd be curious what the results are of that, too!
So my car has the M112 engine with 184,000, km on it. The only speeds I was able to test with today are
Idle 43db
90 km/h 60db
Note though that asphalt/the roads in Lebanon are not the smoothest.
Thanks! Guess your CLK (was it?) is quieter than the C
My idle is around 44db, and interestingly enough, if I rev the engine to 2500rpm while the car is stationary, the car is quieter inside when the hood is OPEN than closed. I was testing this b/c I was bored today. Surprised the F out of me!
With the bad weather I wasn't able to do tests on the road. I tried it with 2 phones and same apps (Sound Meter), first was done with my Samsung S6 and today with S7. Results were a little higher with S7, instead of 30-32DB with my S6, I get 34-36DB at idle, you can barely tell the car is on, I am disappointed in not thinking of a sound meter app when I first started sound proofing my w204 but ever since I own it, the road noise bothered me. All these modifications help me achieve my goals and I can't be happier, I tried the s7 in a 2012 camry 2.5L as well which was around 43db so im confident my results cant be more then +/-2 db off.
If you click the quietest idling cars, obviously hybrids and electric cars with the lowest at 30db and mercedes in general are pretty high in that list, all over 40 except E400 at 37db and w212 E350 at 38db.
Thanks! Guess your CLK (was it?) is quieter than the C
My idle is around 44db
The idle figure I posted btw is with the car in Park. If I put it in Drive, the RPM drops obvisouly and the sound level drops to 41db. I'll post more figures as I keep testing.
The idle figure I posted btw is with the car in Park. If I put it in Drive, the RPM drops obvisouly and the sound level drops to 41db. I'll post more figures as I keep testing.
Weird result! Interestingly enough, when I put my car in drive, the RPM drops and the sound level increases. FML.
I gave up on Youtube. Stupid wind. Anyways, here is the detailed info on the mods I made for my car. The lines in blue is what I added. Enjoy! Apologies my car interior is a mess. Spent the weekend helping some people move to their new house!
Rubber D type seals in both of these locations
2x stacked closed cell foam on both sides of the trunk.
This D type rubber seal runs along side the length of this car, from back near the C pillar to along the A pillar.
This D type rubber seal at the top starts from the rear C pillar/door past the B pillar all the way to the A pillar
The top left rubber bit is pushed out, as suggested by a fellow forum member. I had some left over OEM door seal, so I added this bit to further close the gap.
This is hard to describe. this is the same D type rubber seal used throughout my mod, but this one is on the inside of the door, there is another seal as per my other pic, and once the door closes, the two rubber seals touch, thus causing a very solid seal from both air and noise.
As indicated
This is the rubber D type seal that's on the rear doors. as indicated in my other pic, this seal touches the other rubber D seal on the front doors, thus causing a very solid seal.
Last edited by superangrypenguin; 03-11-2018 at 12:50 PM.
Nice, I put the universal weather stripping at the same spots you did, the front doors needed 2 layers since with 1 strip (12mm thick), when I shut the door with a piece of paper in between, I was still able to pull it out. I uses my foam stripping first and then put the rubber strip on top on it which the 3m adhesive on the rubber seems to stick well on the foam. With two layers I am unable to remove the piece of paper which results in a better seal.
I see you didn't add any to the bottom of the doors and there's also the bottom corner of the door that can use some sealing
As you can see, the headlight seal and hood seal connect.
With all this, engine bay tempratures are the same but it seems like the air box stays even cooler now that the ducts are sealed and all the air is forced to go in the intake ducts.
.
Thanks @ ltwargssf for the suggestions. Definitely a few other ideas there to explore! One of your posts made me laugh a bit. So I went about sealing the hood a bit differently than you. In your post, the second one from the bottom, I simply stuck the D rubber on the fender @ the edge, but the funny thing was when I closed the hood it would just bulge out and thus, since it looked stupid I yanked it off. I couldn't get my rubber trim to stick to the hood itself like you did, but I'll give it a shot again.
Re: the front doors, I see you sealed it near the bottom there. I think I get the same result with the double seal approach I took, but I don't know. I did seriously give the approach that you took about sealing the bottom of the door, but I ended up not doing it, because atm the main source of noise(s) is the engine bay, and the window glass itself because they're single pane. I'm exploring acoustic glass atm and if it's cost effective I may just bite the bullet, but I don't know of any shops that carry it.
I'm debating whether or not I want to put an acoustic blanket attached to the underside of the hood to minimize engine noise a bit further. That said, the main issue there is a potential increase in engine temperatures which would lead to faster wearing, (rubber poly v belts and such). Just thinking out loud, but I think between the two of us, we've probably hit the top 5-10 areas of concern to minimize noise a bit further. I seriously thought about doing some more work on the car today, but my fingers gave out after a while in 3'C temp. I may just wait a few weeks
03-06-2018, 08:50 PM
