Brian GT PRO

Hi guys, I wanted to get some feedback and opinions here.

I have yet to get a C63 in here with headers and no cats, so I decided to use our shop car as a first. My initial impression is that the car is FAR too loud to drive, PERIOD..Is it just me? or an I being over critical? My feeling that with headers, straight pipes leaving the factory resonator and factory exhaust just is tooo ridiculously loud. I feel that I must figure out a good logical way to reduce noise and keep the flow for power.

Those with this set up chime in!! I'd like to know your thoughts.

alqamzi

what was the gains? just put high flow cats and keep the resonators...

nrgy

I have the Long Tubes and 300 cel high flow cats, and I can tell you even with the high flow cats it was still incredibly loud. I sent sound clips to another guy with the LTs and NO cats and he thought my car was just as loud.

HOWEVER, I don't know if there is a break in period with this metallic cats, or I've simply gotten used to the sound, but it seems to have quieted down a bit. Don't get me wrong, it still sounds insane during cold starts and WOT, but I love the way it sounds now. In fact, I almost took my car back the following week to have the stock manifolds and cats put back in place because I had the same reaction as you, but am VERY glad I decided to give it some time.

My suggestion, try the 300 cell high flow cats, let them break in for several weeks, and then see if you don't like the new sound

Dads C63

What did you say????? Can't hear you?????

Try it with no resonators, straight through mufflers and all 3" mandrel bent SS piping. HOLY CRAPP!!

Seriously, with the headers, stock resonators and mufflers it sounds GREAT!! Thats my opinion. Leave it for a while and I think you'll get used to it.

Jons95c36amg

I think the sound of the stock exhaust is loud. It sounds like a aftermarket system. Or maybe its me.

hhughes1

Dad'sC63: full race exhaust as described above....VERY LOUD and VERY FAST
Mine: MHP LT's with stock resonator and mufflers...Loud at WOT and Sorta Fast

Turn it up and hear for yourself

http://www.youtube.com/watch?v=HRyHsrutIvI


http://www.youtube.com/watch?v=O8zDzhqUyOE

C63 Guy

My mom called my car "offensively loud."

So there's that.

Josh

superlubricity

I agree.

JonMBZ

I have heard many people say it is too loud. I love a mean sounding car, but race exhaust just doesnt sound good to me.

Jons95c36amg

These guys want it louder. I just don't like the excessive drone. We are driving a luxury car not a suped up muscle car. Well to each its own.

OverBudget

I have short tube headers, primary cat's left in, secondary cat's removed, and resonator box removed. We put in an X Pipe in place of the resonator box. It's loud above 2,500 rpm's, but it's fine below that. The only time I think the car is too loud, is when I leave my house early in the morning and upon start it rev's loud, stays at 1,100 rpms for a while, before dropping to about 600 rpms. I always hope it doesn't wake or bother the neighbors.

c63ukraine

Anyone noticed that with LT and no cats there is a metal crackle sound that is just drives me crazy. it is not the loudness, it is crackle that I do not like. I wonder, would the removing stock resonator, welding in 2 inline resonators and a true Xpipe will make it quieter and remove the crackle out of the sound?

Brian GT PRO

Thank you to everyone and their input!! in our opinion the set up is FAR too loud to be used daily, so we're working on a few ideas to subdue the sound, and clean up the crackle for guys who need the car a bit more "liveable"

obsidian05e55

Brian, what headers are you running?

Unbreakable1

definitely looking forward to what you come up w/ Brian...chances it'll be fabricated to work along w/ your tune?

HIRO63

Attached product is center muffler that is selling in Japan. Its made for C63. What this is that from inside of the car you just push a botton then 1 valve closes so you can reduce the sound. This is made for people who have to drive home late at night and you dont want to wake people up people put this in. When you are out in road where you want sound all you have to do is push the botton then valve will open so you get good sound.

obsidian05e55

Thats pretty cool..^^ I assume that replaces the resonator?

jrcart

Longtubes, no cats, x-pipe and aftermarket resonators. IMO not too loud except under wide open throttle, around town driving decible levels are very tolerable.

Brian GT PRO

Thanks for your comments guys!! on the headers, they are our own headers, and yes they will be set up to run with our tune.

Hiro63, I have seen that, it is an interesting product to restrict the exhaust flow, hmm this is an idea. I do however want to try to not restrict the exhaust, and what jrcart just said was the next step in our evolution of this set up, however we may also incorporate some highflow cats as well, but this is still on the drawing board.

Sincity

Brian, I was envisioning that you will create a resonator section (like Hiro's post) instead of your x-pipe from prior feedback.

JM

hey brian,

I am running no cats but stock headers but i replaced a downpipe in between... its is extremely loud at the moment, one reason why i probably wont get my headers for a long time...

if you want a video of how it sounds i can link ya

Brian GT PRO

Actually, we are planning a X section before the resonator, coupled with a highflow cat or possibly some sort of pre-resonator assembly, as we feel the car truly needs it, our Double XX without headers is actually the exact sound level I'm trying to achieve, as the Double XX cars actually sound perfect to my ears (tone, and sound level).

obsidian05e55

Any more info on GT Pro's headers? didnt know you guys produced them..

BerBer63

Ill buy a set of LT and midpipe to meet at resonator if its <4k. Deal?

HIRO63

I dont know exactly what it replace with. All it said is center muffler.