Mods for C55 AMG
07-17-2007, 05:48 PM
#26
MBWorld Fanatic!
I'd love to do a full exhaust with headers, as the factory setup looks really awful. I'm used to BMW M's, and the factory headers they have put our AMG's to shame. I've just been hesitant due to emissions crap here in SoCal & some shops look at you funny even if you have a different center or muffler. I REALLY want headers & pipes, but maybe I'll just try modding it from the secondary cats back???
BTW, when under the car this wknd I measured the pipes & found that AMG used 2-1/2" duals from the downpipes back to the Y before the resonator. Then they increased to a 3-1/8" single into the resonator, and a 2-3/4" out (they used metric equivalents of course). Then they Y-off into 2-1/4" duals to the mufflers. I'm a little dissapointed by the small pipes as the system goes back, considering the supposed HP these things should make.
Did you change everything from the secondary cats back to mufflers?
BTW, when under the car this wknd I measured the pipes & found that AMG used 2-1/2" duals from the downpipes back to the Y before the resonator. Then they increased to a 3-1/8" single into the resonator, and a 2-3/4" out (they used metric equivalents of course). Then they Y-off into 2-1/4" duals to the mufflers. I'm a little dissapointed by the small pipes as the system goes back, considering the supposed HP these things should make.
Did you change everything from the secondary cats back to mufflers?
and for this reason I am using two 2.5" dual SS metal cats to a Magna flow SS Y-pipe(Dual 2.5 to 3"single outlet) to a single SS 3" Vibrant resonator. Then from there I have SS 3" pipe going to the Stck muffler for now believe it or not. The car is a little louder than stck but certainly not obnoxious. WOT is a slightly and i mean slightly different story but nothing that would make you say your car sounds horrible.(single exh setup) You add headers THEN the car will be louder but it's nothing like a Chevy or a Mustang loud.(Dual exh setup)
If your car is Dual from the mani back, put a SS x-pipe after you replace your secondary cats with two SS 2.5" aftermarket cats. From the X-pipe I'd run 2.5" SS dual pipes with one SS resonator per side then run 2.5" ss pipe per side going to the Stck mufflers (pipe diam stck may be a tad smaller). You'll have a nice surprise.
07-17-2007, 05:53 PM
#27
MBWorld Fanatic!
Only if they add headers Vadim. When I removed everything ,secondary cats back to bigger secondary's ,bigger diam reso, to 3" piping to the stck muffler my car was nowhere as loud as you may think. Not at all. headers was certainly a different story but it's still not as obnoxious as other V8's or an E60 M5 with a full header back exh system.
07-17-2007, 06:51 PM
#28
Member
Join Date: Aug 2004
Location: Redondo Beach
Posts: 207
Likes: 0
Received 1 Like
on
1 Post
Z06, M3, Mini Cooper S. Sold: C55
Not confident any of them would do much for response on our cars tho.
07-17-2007, 06:56 PM
#29
MBWorld Fanatic!
OK, good it's still a real damper. I've seen more than 1 person ruin their engine by removing a factory damper & just putting a pulley on that does nothing to absorb & reduce crankshaft harmonics! BTW, I wonder if anyone has gone to one of the companies that makes performance racing dampers for American cars? There are some nice designs, such as steel outer shells that enclose a weighted ring suspended in a silicone fluid and mechanical dampers that rely on more than high mass to reduce vibration.
Not confident any of them would do much for response on our cars tho.
Not confident any of them would do much for response on our cars tho.
07-17-2007, 10:10 PM
#30
Member
Join Date: Aug 2004
Location: Redondo Beach
Posts: 207
Likes: 0
Received 1 Like
on
1 Post
Z06, M3, Mini Cooper S. Sold: C55
and for this reason I am using two 2.5" dual SS metal cats to a Magna flow SS Y-pipe(Dual 2.5 to 3"single outlet) to a single SS 3" Vibrant resonator. Then from there I have SS 3" pipe going to the Stck muffler for now believe it or not. The car is a little louder than stck but certainly not obnoxious. WOT is a slightly and i mean slightly different story but nothing that would make you say your car sounds horrible.(single exh setup) You add headers THEN the car will be louder but it's nothing like a Chevy or a Mustang loud.(Dual exh setup)
If your car is Dual from the mani back, put a SS x-pipe after you replace your secondary cats with two SS 2.5" aftermarket cats. From the X-pipe I'd run 2.5" SS dual pipes with one SS resonator per side then run 2.5" ss pipe per side going to the Stck mufflers (pipe diam stck may be a tad smaller). You'll have a nice surprise.
Sounds like a nice setup. I'm tempted to start messing with a custom exhaust, but was trying to avoid too much custom fab. I actually built my own exhaust for a previous car (bought raw tubing, cats, muffs, flanges, and welded it all up), but I vowed to never do that again it was so much work. Maybe if I can find a good CUSTOM muffler shop in So Cal that knows how to do decent welds... and one that does custom headers would be a nice plus...
Question is, at what point does my ECU become unhappy?
07-18-2007, 04:52 AM
#31
Super Member
Join Date: Nov 2004
Location: Los Angeles, CA
Posts: 570
Likes: 0
Received 0 Likes
on
0 Posts
2006 BMW X5 4.8is and 2005 C55 AMG
Not looking to start an argument - but Renntech's site advertises their Stage II for C55 (ECU, carbon fiber airbox, and SS headers - for $8k msrp) adds 40hp and 44 lb-ft of torque... I'd think you'd feel that much of a jump in power, assuming their numbers aren't inflated.
07-18-2007, 05:17 AM
#32
MBWorld Fanatic!
If you are just chging the 2ndary cats to the muffler you should not have to mess with the ECU.
07-18-2007, 06:10 AM
#33
MBWorld Fanatic!
And he also has no LSD. (11.5@123mph 1/4 mile). Enzom PS2's (11.8 @ 118mph stck E55 no LSD). NYC_SRT8 stck tires Goodyr RSA's (245-20-45) No LSD! (12.1@118mph NOS) 1/4 mile. These cars are all using the stck sized tires.Wider tires I don'tfeel are necessary for the C55 and add unsprung weight.
Straight line acceleration and the right tires,stck size,no LSD and not wider tires,car will still run good times in 1/4 mile when car is feathered right coming out the hole.
Here is a fast C55:
headers,ECUairbox,DR's.
https://mbworld.org/forums/c32-amg-c55-amg-w203/191821-one-fast-c55.html
Last edited by ProjectC55; 07-18-2007 at 09:03 AM.
07-19-2007, 07:56 PM
#34
MBWorld Fanatic!
Join Date: Feb 2004
Location: Arizona
Posts: 3,703
Likes: 0
Received 4 Likes
on
3 Posts
SL55AMG, Ferrari 348, Ferrari Testarossa, Ferrari F40, Ferrari Mondial t, Ducati 916, Indycar
We have some ex-AMG software writers working for us. We have developed a very nice ECU tune for the C55 that ads +-35hp, and is priced very competitively.
We have also developed an excellent ECU set up for the C32 that will give you a 12-15% gain.
It seems as though nobody really trys to do much for the C Class AMG cars....well let's try to change that!
Feel free to contact me with questions.
We have also developed an excellent ECU set up for the C32 that will give you a 12-15% gain.
It seems as though nobody really trys to do much for the C Class AMG cars....well let's try to change that!
Feel free to contact me with questions.
07-19-2007, 09:13 PM
#35
Banned
Join Date: Mar 2006
Location: Southern California
Posts: 2,855
Likes: 0
Received 2 Likes
on
2 Posts
S600TT, R350
We have also developed an excellent ECU set up for the C32 that will give you a 12-15% gain.
15% is 52.35 HP.
So you are telling me that for the past 6 years I have been doing everything wrong????
Please, when making BIG HP claims please post before and after dyno.
07-20-2007, 03:16 PM
#36
Super Member
Join Date: Jul 2004
Location: Vegas-Baby
Posts: 615
Likes: 0
Received 0 Likes
on
0 Posts
a Black
07-20-2007, 05:58 PM
#38
MBWorld Fanatic!
Join Date: Jun 2007
Location: Philadelphia, PA
Posts: 2,949
Likes: 0
Received 0 Likes
on
0 Posts
2008 A8L, 2002 996TT X50, 2009 X5
I also noticed, from their site, they talk about a "ECU and pulley" for 55K models - I wonder if they take the same approach w/ C32 - I also wonder if they fab their own custom pulleys, or use someone elses (i.e. ASP, Renntech, Kleemann, evosport, etc.) - it's hard for me to believe a 12-15% gain with ONLY an ECU tune on the S/C engine, but who knows...
