305c55

I'd definately be more interested in Long tube headers....but if the vote swings the other way I'll be down for that too.

alroumi

Estimate cost?, Stainless steel prefferably.

rbaker

This project has gotten rather quiet lately... after totalling the votes & having a discussion with the fab shop, they kind of lost motivation to make these headers with barely 4-5 interested parties, as they would like to do at least 5 sets of headers per run. So for now, I'm going to just close this topic. Also, I've heard there is at least 1 other person on these boards with a header in development, so maybe there's hope for others that want them.

On another note, my car is finished with shorty headers & a full custom exhaust (shortys, 4 hi-flow cats, larger tubing, x-pipe, and true duals). We actually retained the stock C55 mufflers & adapted the inlets to the larger pipes so it looks almost factory. It sounds pretty mean, although I'm debating putting on 2 small resonators to mellow it out just a hair. Cruising is fine, but when I step on it she barks really loud! I'll see if I can post a vid & sound clip later on (in another thread) for anyone interested.
--
Roger

AMGSC

I was thinking about a custom exhaust solution as well. I took my car to Fast Intentions in Northridge (Custom Exhaust Specialists). Dan/Randy advised against X pipes. Any drawbacks of doing this? Did you lose significant backpressure? He also suggested getting upgraded mufflers otherwise it would still choke the flow when it gets to the stock mufflers. Is he making any sense?

c55asleep?

In my setup I have primary deleted then an x-pipe then highflow cats and worked great. I asked here in the forums but no one answered, so I tried it how I just explain trunout was 330wrhp 335trq. Mybe this can help others..

AMGSC

If that's the case, then I'm going through with my plans and will X-pipe my car as well. Did you upgrade your mufflers?

c55asleep?

I have the factory exhuast (amg) to tone it down a bite. Imop the mufflers don't do very much compared to the cats. Btw i have kleemann headers. They delete the primaries and i had done the rear cats and resonator delete,so i had to install the cats after the x-pipe because i was not sure where to put them. Also i tried no cats and just xpipe but to loud so installed the highflow cats.(magnaflow) if you have any concern pm me i will help!!love to hear about your setup

rbaker

Hmm, that doesn't sound logical to me... I've never seen an X-pipe hurt the overall HP output. Also, the factory AMG mufflers are STRAIGHT THROUGH! It seems unlikely that they would hurt power either. Basically if you've seen the inside of a Borla straight though muffler, the stock AMG's are the same, except these go from a single inlet to dual outlets so there's a Y inside. Also, the AMG's have one little trick inside to help reduce resonance/drone... they have a resonant stub pipe inside to help quiet it a bit more by using reflected sounds waves to cancel out some noise. When I did my exhaust, the shop and I didn't see a reason to change them. Only thing, is if you use larger pipe, the shop will have to grind out the inlet somewhat to open it up. AMG pushes the stock exhaust pipe up inside the muffler a bit, and this is smaller diameter than you want. If the shop grinds out the weld, the stock AMG pipe can be slipped out slightly & you'll have a larger diameter inlet. That's what we did...

Also, remember that your car is Supercharged, which makes a slight difference... you have less need for tuning the exh for specific scavenging and more need to just get it out of the engine! Backpressure is a myth and isn't needed...

AMGSC

Thanks for your logical explanation. I will approach Randy again and pass this information to him and see what he says.

rbaker

BTW, run cats, there's no good reason not to... there are plenty of high flow one's out there. I don't think the factory primaries are too bad. Also, if you run aftermarket cats, you WILL get a check engine light, as most of the aftermarket cats are NOT clean enough. They may pass a sniff test, but the computer will not see them cleaning the exhast properly. This can be solved many ways however, simple as moving the rear O2's out of the pipe a little bit, or software change, etc.

My car has headers (did not make it louder), larger pipe (did make it louder), 4hi-flow cats (louder), x-pipe (quieter & changes tone), no resonator (louder) and stock mufflers. Overall, it's a LOT louder now. If I drove it everyday it might be a bit much. But for a weekend car it's probably OK. With a SC, you might want to use some extra "bullet" resonators to help keep it quieter.

AMGSC

Thanks. I am having the Kleemann Cats (combined with Downpipes, Headers and Cams)being installed and resonators removed but did not purchase the Kleemann Cat-Back Exhaust because Vadim thinks they are not worth it cost/benefit wise. I am leaning towards the X-pipes. What diameter exhaust did you go with? I forgot the stock diameter of the C55 exhaust also.

rbaker

The stock pipe diameters change all over the place. I have them written down at home, but if I remember correctly they are approximately:
-From exh man to cat inlet: 1.75" (yes, they're that ridiculously small)
-Cat inlet, 2 steps from 1.75" to 3"
-Cat outlet, 1 step from 3" to 2.38"
-Pipes from primary to seconday cats, 2.38"
-Sec cat outlets Y into a single 3" that goes into resonator (chambered, but with stright flow path)
-Resonator out, 2.75"
-Y from resonator single out back to dual muffs has a single joint as small as 2.25"
-Dual 2.25" pipes to mufflers

Remember this is from memory, and the real pipe sizes are metric equivalent. If you want exact #'s I'll have to check my measurements at home. But those small pipe dia's are the primary reason we decided to change all the pipes when I put headers on. I couldn't see putting headers on & having them connect to 1.75" pipes per side, then go through a single Y as small as 2.25".

I went with 2.5" dual pipes all the way back.

I wonder if AMG will ever bother with a real exhaust (esp manifolds)? From what I've seen, even the 63's have crap manifolds.

AMGSC

Sounds like 2.5 dual pipes makes the most sense to me also. The 3" sections of the stock really have no benefit with the choke points you described throughout the exhaust path. Did you lose much torque?

rbaker

Haven't noticed any torque loss driving around the street, but I still need to log some power curves to see for sure. But really, who cares? AMG's problem is not a lack of torque, it's a lack of high RPM power. That's where they need help. So long as the exhaust adds more up top than it loses down low it's a win.

AMGSC

I went back to Danny at Fast Intentions and am going forward with plans to do the X-Pipe at 2.5in all the way since he advised the same dia. as you. However, can you confirm that the muffler is a straight-through design so there is no need to upgrade? Is that why Eisenmann and Supersprint does not make mufflers for the C55? Why does Kleemann make a muffler for the C55 unless it has better flow? What about getting just the Kleemann muffers/tips without the cat-back pipes so the shop can fab custom dual X-mid pipes all the way back like you did?

StealthAuto

I have C55 headers with a thermal coating available.

Let me know if you guys have any questions.

Sincerely,

Aaron

alroumi

pricing ?

Thank you in advance.

2QUIK4U

Who are they made by?

StealthAuto

For all who are looking for headers feel free to email me and I will hook you up and answer any questions you may have.

Sincerely,

Aaron
Aaron(@)StealthAuto.com