AMG893

Okay
Got the car back today.

Just to clarify this is the setup NOW:

OE Tune
Long Tube Headers
100 Cell Cats
Then the rest is factory with 2nd cat delete and straight pipes in place of that.

Car made 31 RWkW after adding LTH. Still yet to retune. Will do that later this week.

In all the car is WAY too loud.
Before adding the LTH & 100 Cell cats, i only had 2nd cat delete and i was happy with the sound.
Adding LTH & 100 Cell cats, i knew it would be louder. But i didnt think it would be this loud.
Granted driving easy, it OK. Just passable. But as soon as you touch the throttle the sound is very loud.

Anyhow, i am going back into shop, and im going to put my factory 2nd cats back in, in aid to quieten it down a little.

Does anyone have any recommendations?

I noted Wobble64 in the last thread recommended Akra Slip on. Yes they do sound great my friend had that on his C63. But i am wanting to retain as much factory sound as possible.

As far as power goes, i have yet to really drive the car to get a feel for it. Will report back on that. But on my short drives, i really cant feel any more power to be honest.

Also FYI there was no CELs.

So now making 315RWKW.

I will post up results when i get a retune to see if its any better.

Anyhow again, can anyone recommend how to make it quieter?

AMG893

If adding 2nd cats still doesnt quieten down enough, i will try adding my factory cats back on. What does everyone think of that? Or not a good idea?

Wobble64

Long Tube Headers and primary cats are not compatible, as they would go into the middle of where the header is now, before the pipes merge. If you want power and quieten it down, a different rear muffler setup is the solution. The stock mufflers are designed with everything before them in mind - with just LTHs they are too loud, as you found out.
An Akrapovic quietens things down and brings the stock sound back (deep tone). Others, like Eisenmann, may also work, but I do not have personal experience with them.

AMG893

Yes true about LTH & Stock primaries. :banghead:

My car literally sounds like all the YT vids of C63 De-Catted. I guess 100Cell cats are to blame?

Anyhow again, will report back after 2nd cats are fitted.
If still no good i will look into Akra mufflers

Merc63

Get an X pipe.

Kriston

You need Either an Akra or Eisenmann Catback system.


My car with full bolt ons sound very quiet during normal driving. I love the Akra but don't like the square tips. I went with the Eisenmann setup.


Search my posts you will find videos etc of the sound.

AMGonFire

Let us know how it sounds when you put the sec cats back in also do you have the stock resonators in? If not if put those in as well too

BLKROKT

The stock OE mufflers are designed to amplify noise really. An Akrapovic/Eisenmann or valvetronic-type (where you can open or close the muffler valves electronically) such as IPE or FI is your answer.

avery.whss

I highly doubt headers sounds like a de-catted C63 ...I have a fully decatted c63 and headers are ATLEAST 5x louder..Atleast, I laughed though I mean guys on this forum put headers on a 6.3L engine and expect it to not make your ears bleed? I mean REALLY? Is ignorance that rampant?

Its cool you got headers but for real, I swear every day theres a thread "Cars too loud! just have 2nd cat delete!" If the cars to loud..go drive a tesla..

im pretty sure you'll have a hard time even putting the 2nd cats back on, atleast thats what a shop told me when they measured the headers length ...basically you have to go headers > xpipe or something else

layzie12g

X pipe will change the sound of the car. My car is straight piped with no resonator and it is loud at wide open throttle.

Ihopaz

X-Pipe will help! Try that before putting money into aftermarket mufflers!

gzim335

What about ur imaginary whp numbers lol

Ihopaz

Exactly, my car no headers yet just with resonator and second cat delete with a tune AND an X-pipe is loud at wop. I've heard videos of the same setup and headers from a member here and it confined that I want headers.

This is a great well tuned big engine, you have to know it's going to be LOUD! I think one set of cats and an X-pipe is the quietest you will get it. Understand the more you quiet it down the more you restrict the flow and defeat the purpose.

AMG893

Merc63- That will be my next step after putting 2nd cats back in.

Kriston- I may need to do this in the end. I wanted to spend as little as possible. Akra (which i actually love the square tips) are so pricey! Thing is i want to retain as much of the AMG rumble as possible.

BLKROKT- Read above.

Avery- Well looking at the vids on YT, i can say at WOT etc it sounds the same of the decatted vids. I havnt heard a decatted C63 in person, and i know sound on computer speakers is different from real life. But it sounds very similar. Its very loud. Though i will say there is no drone which is good.

Ihopaz- Yep, trying everything before having to shell out $$$ on mufflers.

gzim335- LOL.

Ihopaz- Yeah im trying to find a good balance

Magno507

Which LTH did you go with mate??? put a video up

AMG893

They are just XFORCE ones.
Nothing special.
4 into 1. Nicely made.
Will post a vid in next couple of days.

AMG893

Here are some pics of the headers for those interested.

Going in tomorrow to have 2nd cats put back on.

roadtalontsi

I've never heard long tubes with cats in person, but i've heard long tubes with no cats and stock manifolds with no cats and It's horribly loud even at cruise. And it's not really a good kind of loud. It's very raspy and bleh. I can tell you the akrapovic does wonders. only loud when you're getting on it.

AMG893

Yes it really is horribly loud.
At cruise its actually ok. Just after 2500 rpm is when it gets loud and raspy. Not in a good way.

AMGonFire

Not sure if this could work but what about adding some bullet mufflers mid in the pipe or wherever best fits could quiet it down

Mikegpr03

Pm me
Put a 3inch H in

AMG893

I have a set of aftermarket resonators here, which if need be i will fit also.
1st step see how it goes with the factory 2nd cats.
Then keep going from there.

I wonder, does anyone here (or know of any vids) have this setup:
LTH
Primary cats
2nd cats
resonators
stock mufflers
??

Thanks

AMG893

this is current

Kriston

I wont waste time with H pipes and Resonators. They will assist but will also block up the free flowing exhaust you just installed.


I went with Highflow Cats + aftermarket catback and its perfect now. Tried the H pipe and it was still loud.

09whitec63

How did the x force fit?? The price is really attractive that's for sure