More exhaust note
Thread Starter
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CLK 55 AMG 2005 and CLK 63 AMG cab.2007 - 2009 EVO - 2013 ML63 AMG - 2018 G63 AMG
thanks for clearing that up for me 
Now, how can I find out what diameter is my 2nd cat/ converter?
on a 2005 CLK 55 AMG ??
is there an easier way to find out w/o going to a muffer shop?
Now, how can I find out what diameter is my 2nd cat/ converter?
on a 2005 CLK 55 AMG ??
is there an easier way to find out w/o going to a muffer shop?
Member
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From: NJ
R8 V10
Your car has 4 cats, two primaries / two secondaries (one per side each).
The primaries have O2 sensors before & after. The secondaries are much further back in the exhaust system (look at picture provided above).
No, its not "best" to change primaries. Changing primaries is a huge headache b/c you have to worry about check engine lights and etc. also the primary cats are actually less restrictive than the secondary cats. Hope that helps. Get the 300-cell secondary cats, they won't disappoint
~AMS~
The primaries have O2 sensors before & after. The secondaries are much further back in the exhaust system (look at picture provided above).
No, its not "best" to change primaries. Changing primaries is a huge headache b/c you have to worry about check engine lights and etc. also the primary cats are actually less restrictive than the secondary cats. Hope that helps. Get the 300-cell secondary cats, they won't disappoint
~AMS~
Is all of this info true for the 500 motors as well? I want to wake up the exhaust note on my CLK500...will the 300 cell cat do this? Do you by any chance have any sound clips of this?
Thanks
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AMG
The best thing for your car is our Stage 2 performance package (headers & pulley) that will wake up the car the most for sure especially in conjunction with high flow 2nd cats and AMG catback res/muffler. Contact us for more info.
~AMS~
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AMG
~AMS~
Thread Starter
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CLK 55 AMG 2005 and CLK 63 AMG cab.2007 - 2009 EVO - 2013 ML63 AMG - 2018 G63 AMG
Hi AMS,
You told me a month ago to change
my High Flow Cat (2nd cats) ... (to improve sound, flow and HP)
I'm still on stock headers
On my W209 2005 CLK 55 AMG (quad)
I took mesument yesterday to make sure:
2nd Cats is 2.5" in/out
resonator is 3" in/out
I have removed my resonator last year... ( don't know
if it matters in this decision but...)
I'm ready to change my 2nd cats to hight flow 300 cell I think you recommanded...
Ebay LINK
I have taken pictures of my bottom: Is that what 2nd cats are?? 3rd pic
Picture are Front to Rear of the car ( Headers to exhault)
I'm just checking is everything is correct before I pull the trigger.
Thanks
You told me a month ago to change
my High Flow Cat (2nd cats) ... (to improve sound, flow and HP)
I'm still on stock headers
On my W209 2005 CLK 55 AMG (quad)
I took mesument yesterday to make sure:
2nd Cats is 2.5" in/out
resonator is 3" in/out
I have removed my resonator last year... ( don't know
if it matters in this decision but...)
I'm ready to change my 2nd cats to hight flow 300 cell I think you recommanded...
Ebay LINK
I have taken pictures of my bottom: Is that what 2nd cats are?? 3rd pic
Picture are Front to Rear of the car ( Headers to exhault)
I'm just checking is everything is correct before I pull the trigger.
Thanks
Former Vendor of MBWorld
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AMG
The Primary cats are the first pic, These are the second cats below:
Correct, on the W209s its 2.5/2.5 is the proper sized cat (OEM piping is slightly smaller actually, but 2.5" is the closest size) I see you have also deleted your resonator and put a straight pipe in its place, removing the second cats will give you a more full sound with the OEM muffler and should sound nice. Keep in mind, with the high flow cats it will take a good 2-3 weeks for the full sound change to complete, its not an instant change. Over the coming weeks you will begin to notice the transition as the ECU adjusts.
The next biggest difference in power & tone is definitely with the headers. It will make your CLK55 sound much more like the 63, when you are read for those let us know. hope that helps,
~AMS~
Correct, on the W209s its 2.5/2.5 is the proper sized cat (OEM piping is slightly smaller actually, but 2.5" is the closest size) I see you have also deleted your resonator and put a straight pipe in its place, removing the second cats will give you a more full sound with the OEM muffler and should sound nice. Keep in mind, with the high flow cats it will take a good 2-3 weeks for the full sound change to complete, its not an instant change. Over the coming weeks you will begin to notice the transition as the ECU adjusts.
The next biggest difference in power & tone is definitely with the headers. It will make your CLK55 sound much more like the 63, when you are read for those let us know. hope that helps,
~AMS~
Last edited by AMS Performance; Aug 26, 2009 at 03:35 PM.
Super Member
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Posts: 613
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From: Sparks, NV
03 CLK 55 AMG, IMCO muffler/Magnaflow tips, KW V1 coilovers, 19" Petrol Metrix Wheels
my car sounds very deep and throaty and i did not touch any of my cats or resonators. upgrade just your muffler to a four chambr muffler: magnaflow, flowmaster, IMCO, etc. the car will be plenty loud and will definitely sound the part. Plus you will spend less than $800 for parts and labor.
you dont want someone hacking up the mandrel bent exhaust AMG so graciously supplied you. 3in mandrel bent exhausts are about as good as it gets from the factory. unless you are racing leave the cats alone.
you dont want someone hacking up the mandrel bent exhaust AMG so graciously supplied you. 3in mandrel bent exhausts are about as good as it gets from the factory. unless you are racing leave the cats alone.
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Former Vendor of MBWorld
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AMG
my car sounds very deep and throaty and i did not touch any of my cats or resonators. upgrade just your muffler to a four chambr muffler: magnaflow, flowmaster, IMCO, etc. the car will be plenty loud and will definitely sound the part. Plus you will spend less than $800 for parts and labor.
you dont want someone hacking up the mandrel bent exhaust AMG so graciously supplied you. 3in mandrel bent exhausts are about as good as it gets from the factory. unless you are racing leave the cats alone.
you dont want someone hacking up the mandrel bent exhaust AMG so graciously supplied you. 3in mandrel bent exhausts are about as good as it gets from the factory. unless you are racing leave the cats alone.
You have it backwards... the LAST thing you should ever touch is the AMG rear muffler, its the best part of the entire system and is 100% free flowing as is. Everything in front of the resonator is not AMG, its bone stock off the shelf mercedes parts from the lower non AMG models (in this case the 500). Therefore, that is the most crucial part of the system that needs upgrading. High flow secondaries (or delete) are a must if you want more power an sound. Bolt-on Shorty headers are the best solution for those not wanting to chop up their stock systems and want a 100% bolt on design. The resonator is 100% free flowing as well so no point in touching it. Headers & high flow cats are all you have to do on the newer amgs, leave the rest alone.
Thread Starter
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CLK 55 AMG 2005 and CLK 63 AMG cab.2007 - 2009 EVO - 2013 ML63 AMG - 2018 G63 AMG
Is this mod really deleting the 2nd cat...?
cause I think it's more like replacing the 2nd cat for a high flow one
cause I think it's more like replacing the 2nd cat for a high flow one
Super Member
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From: Sparks, NV
03 CLK 55 AMG, IMCO muffler/Magnaflow tips, KW V1 coilovers, 19" Petrol Metrix Wheels
dude if you want to sell your cats and headers that is one thing but dont be silly. The stock AMG muffler provides zero sound, zero. If it is not allowing sound it stands to reason there is baffling and therefore it is restrictive. This is exhaust 101.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
To take things one step farther you guys should do your research on AMS Performance before you begin buying his products or accepting his advice at face value. All public and availble on this forum via the search function.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
To take things one step farther you guys should do your research on AMS Performance before you begin buying his products or accepting his advice at face value. All public and availble on this forum via the search function.
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AMG
AMGgoodness,
I do mean this in the most polite way possible, you are 100% incorrect.
Your stock cats & header are essentially worthless and they are not AMG to begin with, they are 100% identical to the CLK500 components, they sell for next to nothing because they are not AMG (they are stock Mercedes). The only AMG components are the resonator & the rear muffler. You cannot make any more power out out of the rear muffler/resonator, all the power is the cats & headers.
The stock muffler is 100% free flowing design and lets plenty of sound out. it is the headers & cats that really restrict much of the noise (and to some extent the resonator). If you are going to upgrade sound, you might as well make power at the same time. The stock muffler can get very loud if you open up everything before it. The last component you should ever touch on the AMGs is the rear muffler, it is by far the best design. Everything else before it... that's a different story.
The only real way to make any power on these AMGs is with headers & high flow cats. In fact the worst modification HP/$ is rear muffler, they make zero power and cost too much for that zero gain in performance.
Cats are not expensive at all, they are $180 for the pair and $120 to install, so for $300 you get 10HP/12TQ, how is that a bad deal again? Furthermore, Headers cost only $1250, and 4 hours of labor. In the world of Mercedes that's a bargain and a half.
These are the facts, simple as that. Hope that helps correct any of your misconceptions you may have read.
~AMS~
I do mean this in the most polite way possible, you are 100% incorrect.
Your stock cats & header are essentially worthless and they are not AMG to begin with, they are 100% identical to the CLK500 components, they sell for next to nothing because they are not AMG (they are stock Mercedes). The only AMG components are the resonator & the rear muffler. You cannot make any more power out out of the rear muffler/resonator, all the power is the cats & headers.
The stock muffler is 100% free flowing design and lets plenty of sound out. it is the headers & cats that really restrict much of the noise (and to some extent the resonator). If you are going to upgrade sound, you might as well make power at the same time. The stock muffler can get very loud if you open up everything before it. The last component you should ever touch on the AMGs is the rear muffler, it is by far the best design. Everything else before it... that's a different story.
The only real way to make any power on these AMGs is with headers & high flow cats. In fact the worst modification HP/$ is rear muffler, they make zero power and cost too much for that zero gain in performance.
Cats are not expensive at all, they are $180 for the pair and $120 to install, so for $300 you get 10HP/12TQ, how is that a bad deal again? Furthermore, Headers cost only $1250, and 4 hours of labor. In the world of Mercedes that's a bargain and a half.
These are the facts, simple as that. Hope that helps correct any of your misconceptions you may have read.
~AMS~
dude if you want to sell your cats and headers that is one thing but dont be silly. The stock AMG muffler provides zero sound, zero. If it is not allowing sound it stands to reason there is baffling and therefore it is restrictive. This is exhaust 101.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
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03 clk55 amg
hey AMS. i have an 03 amg 55 which have the dual tip single exhaust setup unlike the 05 amg 55's, which have the quad tip dual exhausts.. i want my car to sound meaner but wanna keep my amg parts, the headers arent worth it to me, but id be willing to buy a high flow cat to replace my 2nd cat, the question is.. will it make the car sound noticeably "meaner" or will it be more of a subtle change
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AMG
hey AMS. i have an 03 amg 55 which have the dual tip single exhaust setup unlike the 05 amg 55's, which have the quad tip dual exhausts.. i want my car to sound meaner but wanna keep my amg parts, the headers arent worth it to me, but id be willing to buy a high flow cat to replace my 2nd cat, the question is.. will it make the car sound noticeably "meaner" or will it be more of a subtle change
hope that helps.
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From: Woodland Hills, CA
1999 e55 (past), 2002 CLK55 (past), 2004 E55 (present), 2008 Z06
I'll just throw my opinion into the ring. As someone who has had two muffler setups on my E55--first a magnaflow and now a reums--and heard multiple vehicles that have eliminated catalytic converters, I can tell you I have only noticed a dramatic change in exhaust tone when the rear muffler is switched out.
Whether or not an aftermarket muffler makes power, is the most "free flowing," or the cheapst mod are different issues and not really relevant to the original post, which inquired into exhaust sound. Also, people may want to take into account that when you go to sell the car, your future purchaser may we weary of a hacked up exhaust system.
To the OP-if you are really interested in the differences these exhaust mods can make, I suggest you search on youtube. There are plenty of exhaust videos for N/A 55 engines.
Personally, I like my remus, but regret not ponying up the additional dough for an eisenmann sport.
Also, with respect to AMS, if you have access to a video with what an AMG muffler sounds like after cats and headers, post it please (btw- thats not a challange, i would really like to hear it). I think it would provide some valuable information for everyone. Personally, I've never heard one on the 55 n/a motors that sounds decent. FI 55's, i.e the sl55 muffler is another story of course....
Whether or not an aftermarket muffler makes power, is the most "free flowing," or the cheapst mod are different issues and not really relevant to the original post, which inquired into exhaust sound. Also, people may want to take into account that when you go to sell the car, your future purchaser may we weary of a hacked up exhaust system.
To the OP-if you are really interested in the differences these exhaust mods can make, I suggest you search on youtube. There are plenty of exhaust videos for N/A 55 engines.
Personally, I like my remus, but regret not ponying up the additional dough for an eisenmann sport.
Also, with respect to AMS, if you have access to a video with what an AMG muffler sounds like after cats and headers, post it please (btw- thats not a challange, i would really like to hear it). I think it would provide some valuable information for everyone. Personally, I've never heard one on the 55 n/a motors that sounds decent. FI 55's, i.e the sl55 muffler is another story of course....
Last edited by jordanst2; Sep 18, 2009 at 11:32 AM.
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AMG
Sure, there are a bunch on the W210 E55 AMG section, some really good sounding videos. Honestly I think the W210 E55 AMGs with modded exhausts are the best AMGs I've heard, I never liked the SC AMG exhaust notes to be honest, I don't think any of them sound any good, too loud, obnoxious & unrefined most of the time.
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E60 dinan M5,E46 M3 track toy,209 CLK55 DD
dude if you want to sell your cats and headers that is one thing but dont be silly. The stock AMG muffler provides zero sound, zero. If it is not allowing sound it stands to reason there is baffling and therefore it is restrictive. This is exhaust 101.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
Whether the rest of the exhaust system is off the shelf or not it is a mandrel bent 3in exhaust. any cutting on the cats and that is destroyed. so unless you are going full on with headers, etc. what is the point of cutting it up.
not only is the stock muffler ridiculously quite it also weighs a ton. So again if all you want to do is unleash the agressive sound of the AMG V8 a muffler is not only your best option it is also the most cost effective option.
Headers and cats are much more intrusive and labor intensive. not to mention expensive. i have been down this road with other cars and in the end it is not worth it unless you plan on tracking the car.
Last edited by the weiner; Sep 18, 2009 at 03:06 PM.
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AMG
Do we have the same muffeler?!?! My AMG muffeler weights next to nothing, I am sure whoever you had "hack up" your AMG exhaust (which you are warning the OP against by saying free flow cats or headers will do yet, you "hacked up" the only part of the system worth anything) really knew their stuff didn't they? Honestly if you were to take just the AMG muffeler ie cut the piping right at the start of the muffeler and weight it, it is only a few pounds and is a beautiful peice of work. Headers are a huge gain, your cheap magnaflow muffler yeilds nothing (louder is not faster) and IMO no other tips I have seen look half as well on a Benz. Sure the headers cost a decent amount but so did your car, none of what you said made sense, how would unbolting a stock set of headers and bolting on a different set be considered hacking anything? As for the cats, sure you are "hacking" off the stock ones but you are welding on replacements and to the untrained eye they would still look stock, are not the stock ones welded on or did they grow out of the ground already attached to the piping at the Mercedes farm waiting to ripen and be picked? So to your resale comment I have a slight feeling that an AMG with a well know companies headers which can barely even be seen from under the hood and a set of cats that could easily pass for OEM would be less of a turn off to an AMG prospective buyer versus an AMG with an off the shelf generic Pepboys Magnaflow muffeler.
All Valid points. The stock AMG Muffler is the best there is really. It sounds great once you open up the rest of the exhaust system. High flow secondaries (and primaries should you chose) + a nice set of bolt on headers will transform the sound much more than most would think. Even with stock resonator & muffler, If you do our bolt on headers & high flow 2nd cats you will definitely get the sound you want. For maximum power, do headers and 4 high flow cats (both primaries & secondaries).
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E60 dinan M5,E46 M3 track toy,209 CLK55 DD
All Valid points. The stock AMG Muffler is the best there is really. It sounds great once you open up the rest of the exhaust system. High flow secondaries (and primaries should you chose) + a nice set of bolt on headers will transform the sound much more than most would think. Even with stock resonator & muffler, If you do our bolt on headers & high flow 2nd cats you will definitely get the sound you want. For maximum power, do headers and 4 high flow cats (both primaries & secondaries).
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AMG
~AMS~
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2014 E350 4Matic
Great thread and lots of good advice regarding how and what to improve on an AMG exhaust. From personal experience on my C43 (sold) I agree 100% with AMS -- leave the cat back part of your AMG system alone. On my C43 I replaced the resonator and mufflers with a BMS system; it was very loud, did not produce much power and, in the end, was too loud for me so I sold the car.
Currently on my C55, I have the Kleeman long tube headers that required the deletion of the stock primary cats. So far I love the mod, I've not dynoed the car yet but sense that this mod has made a hp improvement over the previous evosport shorty headers that I had -- the evo's made at least 20 to 25 hp over stock (last dyno with all mods produced about 425 hp crank). The sound, however, with the Kleemann's and no primary cats is fantastic, much more refined than stock, a little higher, a lot tighter and much like a Ferrari with no increase in interior noise. I've received two glowing compliments on the sound in the one week since the install.
My questions are, with my current set up, 1) would I gain any HP by switching out the stock secondary cats for the high flow SS, metal base, 300 cell cats recommended by AMS? 2) do you think that doing so would increase the interior noise level much, if at all? and 3) do you think that swapping out the secondaries would degrade the sound of my current refined exhaust note, or increase the exterior sound level much?
Note: 2yrs and my AMS crank pulley is running strong with no problems.
Currently on my C55, I have the Kleeman long tube headers that required the deletion of the stock primary cats. So far I love the mod, I've not dynoed the car yet but sense that this mod has made a hp improvement over the previous evosport shorty headers that I had -- the evo's made at least 20 to 25 hp over stock (last dyno with all mods produced about 425 hp crank). The sound, however, with the Kleemann's and no primary cats is fantastic, much more refined than stock, a little higher, a lot tighter and much like a Ferrari with no increase in interior noise. I've received two glowing compliments on the sound in the one week since the install.
My questions are, with my current set up, 1) would I gain any HP by switching out the stock secondary cats for the high flow SS, metal base, 300 cell cats recommended by AMS? 2) do you think that doing so would increase the interior noise level much, if at all? and 3) do you think that swapping out the secondaries would degrade the sound of my current refined exhaust note, or increase the exterior sound level much?
Note: 2yrs and my AMS crank pulley is running strong with no problems.
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My questions are, with my current set up, 1) would I gain any HP by switching out the stock secondary cats for the high flow SS, metal base, 300 cell cats recommended by AMS? 2) do you think that doing so would increase the interior noise level much, if at all? and 3) do you think that swapping out the secondaries would degrade the sound of my current refined exhaust note, or increase the exterior sound level much?
Note: 2yrs and my AMS crank pulley is running strong with no problems.
Note: 2yrs and my AMS crank pulley is running strong with no problems.
Hello Tump,
Glad to hear yet another happy AMS customer
. YES, upgrading your secondary cats will make a huge difference especially since your primaries are already removed. The 300-cell metal core cats will highly improve airflow while still keeping the exhaust note refined and also keeping your emissions clean. Typical gains on a stock exhaust are 10HP/12TQ (dyno proven). Now with your setup I wouldn't be surprised if you get 13-15HP/15+TQ. The good thing about the 300cell cats are they do not lower backpressure too much but still keep gas velocity high thereby producing power at all rpms, without sacrificing any low end power. Regarding sound, Don't worry the upgrade to 300-cell cats don't make too much of a difference during normal driving. You do hear more bass but very little of it is drone. Most of the sound change is at WOT. Basically its quiet normally and loud only when you want it to be. Its definitely much better than doing a 2nd cat delete (especially in your situation). Plus for the money not many mods can beat those power gains.
Hope that helps,
~AMS~
