Kevwood

The muffler is pretty much the same as an other chambered muffler, you can stick a camera in there but you aren't going to see much. That being said, the size/volume of the OEM muffler is pretty big to aid in the flow but it's still the most restrictive part of the exhaust.

Yes, ditch the OEM muffler and go with an aftermarket free flowing design, that seems to be where the highest gains are. Tubular exhaust manifolds, secondary cats and OEM resonator delete is (as Carlos mentioned) mostly just for tone enhancement, maybe a total of 3 or 4hp, nothing you'd ever notice.

BHeart

Well said...

Kevwood

Thanks. This is being built for the track so lap times are the most important thing to me, half car, half driver.

BHeart

It is always a two part equation. Which is why I also use my dynos as merely a way of tracking vehicle progress (not as an end-all-to-be-all).

Kevwood

You and me both. Final dyno numbers are like cars themselves, not actual measurments of performance - the driver is the biggest 'mod' to the car. In the group I race with here some of the 'supercars' you expect to lead laps and times don't measure up to cars 20 years older than them with half the horsepower. All part of the fun.

BHeart

And that is so very true. The most capable vehicle in the wrong hands will look like the worst in short order. Just as the most average vehicle in the right hands can produce more than most would ever expect.

Kevwood

One thing that I did not list in this thread were the Magnaflow part numbers, I've got plenty of PM's asking for them so here they are;

12288 - This is the dual 2.5" in, 3" out muffler used in place of the resonator.

12267 - This is the 3" in, dual 2.5" out used in place of the factory muffler.

Both of these are of course free-flowing, non-chambered. I was only on planning on using the 12288 but the system was so loud (with the AMS manifolds) that I had to add another muffler to the system. As you see in my first post write up, the addition of the second muffler did not effect the fnal dyno numbers what so ever.

lazlion99

Kevwood, it seems to me there is nothing to shield the sparetire well from exhaust pipe on passanger side. Does it concern you?

Kevwood

Not at all, the majority of the heat is gone by the time the exhaust gasses pass through the second muffler, after that the remaining heat isn't enough to cause any damage to the wheel well.

If you look at the pictures (they were taken a week or so after the system was done, I was just in for a re-check) you can see the color of the pipe from the front to the rear muffler, it has a gold hue to it. However, notice the color of the wrap around pipe, it's still quite silver looking - this is because the heat is far less and it hasn't discolored yet.

So again, no worries from me, it's a-okay as is, if it was going to be a problem it would have been while I was on the dyno for 3 hours tuning - no airflow to speak of under the car

lazlion99

That helps me deciding on what parts I have to buy.
Thanks!

Kevwood

No problem, looking forward to your pics after the job is done.

Kevwood

Hey pal, really sorry for missing this question!

The answer is yes, the wrap around piping is 2.5", not 2". Because the single 3" splits into dual 2.5" inside the muffler I wanted to keep it nice and open so there would be absolutely no chance of restriction. The muffler directs even flow through both outlets so you don't need to worry about balancing it out yourself. Here is a very crude picture of what the 12267 looks like inside;




Hope that helps.

sleepyheadzzz

were u able to take a look inside the two 2ndary cats? i heard they are completely hollow and are really just resonators...is that true?

Kevwood

They were actual cats, I think all 500's are the same then the 550's only had primary cats, bubble resonators were in place of the secondaries.

I am now trying to find out what the actual cell count of the primaries are, 300, 400, 600 etc. I believe I can pass O2 with a set of 300's so if mine are higher than that I'd like to switch them out before I fit the supercharger.

Really tough to get definitive answers, so far 3 different answers from 3 different groups at MB

betrezra

For those wanting the klee mid-length headers, there is a special tune to elim CEL and make everything ready for emissions...... and back in the day the mustang crowd used to weld in cat shells in the downpipes to pass visual. All of this is for "track use" only of course.

GL.

2MCHCAR

The cell count info will be greatly appreciated Kev!
Keep us posted!

Kevwood

No worries Carlos, as soon as I have verified info I'll post it up.

Classic

I must have missed it but what is the part # for the magnaflow muffler you have in the middle of the car?

Thanks

Kevwood

Here you go.

Classic

Wooow I can't believe I didnt see that lol I just read the 1st page and went straight to asking you lol but thanks man I appreciate it

Kevwood

No worries, good luck.

grech

Kev! You may have missed a question from me in the Magnaflow 14816 thread, I'll just repost my post here since it's related

Thanks to all the info in exhaust threads and especially yours, I've finalized 14263 (couldnt find non-polished in this config) as replacement for OEM muffler. What do you think? Would center inlet/offset outlet be better in any way?

I'm still contemplating a 12216 muffler to put where my resonator was. The resonator is 15'', and this was the only 14'' appropriate fit. 2nd option is to get an 18'' oval Magnaflow with two inlets and one outlet to replace the resonator AND the Y pipe, just like you advised me to do. However I need to get the car on the lift first and measure the exact length to determine whether i need the 14'', 18'', or 24'' body length mufflers.

I actually ordered the 35168 tips for my E class last year but never got to put them on. I'm still divided between sticking with original tips so I dont have to cut the muffler, or these 35168 tips, or anything else. What was the part number of your tips?

PS: When are we meeting up in Doha!

togaclk55

The cats are somewhere in the 400-600 cell range. I'm running 300-cell metal core cats as primaries and no O2 issues.

Kevwood

Hey Talha,

You should be fine with 14263 but next time just ask me to bring a muffler over for you mate, I could have got you the plain stainless version through a supplier here. Anyways, the center in offset out is a nice design because it controls volume better than a center center muffler. I used center offset Magnaflows on my track car in Canada and even recommended them to Wes, he ended up using them too IIRC.

As for the tips, I'm not using Magnaflow, they have a set that is almost identical to the Black Series style but I find them too narrow. I ended up going with a set of tips from Fox, they look a lot beefier IMO. And as for Doha, I'll definitely let you know when I'll be back, it's usually every second week for a couple days.

I have been told by some sources they are 400 and others say 600. The information I am trusting right now is from the MB service shop manager here in Dubai, he worked with MB back in the UK before transferring here and has been with the company for 18 years. He said the Euro & GCC spec cars (as mine is) have 600 cell cats and the US & Canada specs have 400 cell. I believe that this is one of the reasons why my car dyno'd lower than other 500's in North America, 600 cell cats with 100,000km on them have got to be a little more restrictive than a set of 400's with far less milage.

I'm going with a set of 100 cell metal core cats with my Kleemann install so the restriction will be absolutely minimal.

midnight AMG

heya did you ever post a sound clip??