saint13

+1

Pick up a set of 100 or 200 cell cats and try that. I added 200 cell cats between my LTHs and X-Pipe it makes a significant difference - still crazy loud but not quite ears bleeding loud like it was before. Use clamps instead of welding and you can go back if you dont like the sound or want to go for an akra catback later.

Kriston

The High flows act as resonators as well.

ArmoE55

Add cats and you should be good. That will quiet it down quite a bit.

I'm the opposite, when I drive my cars, I want it to be loud and obnoxious- that's the point other than power! My neighbor across the street has a Harley that makes my house shake.

Robert AMG

iTrader: (1)

thanks for all input guys, i will not go with valve mufflers or akra cause of the high cost, i think i will add high flow cats with clamps.
my car rpm at cold start up is at 1700, so imagine how the neighbors are happy.

sirius9

Save up for Akrapovic Cat back. That will solve your problem without compromising your bhp gains from the headers.... You get quieter sound and increased flow and bhp. Win-win!

Kriston

And its almost 50 lbs lighter compared to the factory setup

AMGMD

iTrader: (1)

I just installed MBH LTH, Cats, midpipes and xpipe along with an OE Tune reflash. Install was done Monday 8/22/16. I think it sounds perfect. Zero drone when driving normal and mean when you get on the gas. Car scares me again like when I first got it. Makes me nervous when I sit down and getting ready for a drive. Flooring in 2nd gear 4.5-5k rpm feels like someone kicking you in the back. So glad I have 275s MPSS and Quaife LSD in the back. Made some videos the night I had everything installed...the new setup sounds perfect to me, stock when cruising, aggressive when on it. Can control the volume with your foot and drive settings (c,s,s+,m). Maybe adding cats and an xpipe may help tone the sound down? Here is a link....

Robert AMG

iTrader: (1)

just want to add that also with the free flow headers and no cats the engine oil temperature went slightly down.

chrisridebike8

Are you sure the ambient temps just didn't go down? I thought for awhile my car was running hotter but the ambient temps were in the high 90s and low 100s. Now they are 70s and 80s and the car runs soooo much cooler. I'd be willing to bet it is more a product of the air temp rather than the headers. If anything, my car seems much hotter under the hood now when I open it after a drive.

Robert AMG

iTrader: (1)

i noticed it while driving, so outside air is cooling the engine compartment, not when stationary or in traffic, where i live we have a nice road uphill with corners going from sea level to about 5000 ft elevation in 20 minutes, there where i noticed the engine oil temp went down.

BLKROKT

It's well known that LTH make under hood temps higher. I don't see how it's possible for them to lower your oil temps. Completely unrelated. Coincidence.

Tlnt60

Noticed no difference in oil temps, just hotter under the hood. However I live in Phoenix so hottererer than hot here. I have LTHs HiFLo and secondary delete, sounds exactly as it should IMO. Quite's down when you want it to and screams when you feel like remembering why we bought the car!

INS1GNIA

Hehehe...

Vpatriota

Had to stop reading the whole thread to giggle here. lol.

Vpatriota

Sorry to ask such a dumb question, but what brand are those headers? LT is a brand? I've read people talking about the MBH headers.. Are those the same? Forgive the ignorance.

chrisridebike8

LT = Long Tube headers. As opposed to mid-length or shorties. Plenty of brands for headers. MBH are actually tri-Y headers, not LT headers like many peole think.

BLKROKT

MBH are still considered Long Tube Headers. The type of LTH is just Tri-Y as opposed to 4-into-1. Shorty or Mid-length headers are not LTH, they are as described.

Vpatriota

Thanks for the answer and the patience. Trying to read the most out of the subject "headers/exhaust/tunes" for the M156.

chrisridebike8

According to our sticky, MBH are full length headers but not long tubes. Full length denoted the final collector being after the last bends. Long tube denotes the collector being after all bends. Both are great designs. Just a little terminology. And in all honesty, I'm going solely off the info in the sticky...

https://mbworld.org/forums/c63-amg-w...manifolds.html

BLKROKT

Yeah, I know it doesn't really matter what you call them. But they are considered "full length" or "LTH". At least according to Hot Rod. http://www.hotrod.com/articles/how-t...-right-header/

MBH motorsports

This is literally stupid. Not what your saying but how that thread tries to create a definition. We run 3 collectors in our C63 long tube headers. With the last of our collector after the last bend. We also have an S55 long tube header that has crazy long primary tubes. Some of the tubes have something like 3+ feet in tubing in just one primary tube. Yet we didnt put the collector under the car so people who are lowered didnt bash their expensive headers off a speed bump.
We also have crazy long headers for the G55 but the last bend is after the collector. Point is you can have long tube headers without some made up definition about where a bend is. I could just **** the collector a different way and all of a sudden (by this definition) I have a long tube header. Really it makes no sense.