so my clk63 bs has long tube headers , 200 cell cats , original resonators and mufflers . The dang car is tooooo loud . Magma flow makes a 2in 2 out muffler that I could put in the center maybe in exchange of resonators . Has anyone done this or how can I get this quieter without robbing too much hp. I'd rather have quieter exhaust then nascar hp . And I'm not putting back on the original headers , because I do t have them .

Resonator will solve your problems the 63s are all very loud. Surprised that yours is so loud with cats and stock res/exhaust.

Is it too loud for the track sound limit restrictions or just your normal driving on the road?

A friend of mine has the same set up on his i.e. long tube headers/200 cell cats and the car is too loud for me and I like loud....lol

I had evosport long tubes, no cats, and evosport exhaust my car if I was driving normal was quiet and throaty unless you got on it. Then on the highway was perfect at cruise just like a stock 63 zero drone at all. As you know n/a 63s are not exactly quiet to start with all stock at WOT.

MOFLO, it's too loud all the time .

I tried a Vibrant flow through resonator to quiet down my C32 and it didn't do ****. Eventually it rusted and broke off.

That's when I installed a magnaflow 400cell cat where the resonator was. Made a big improvement; less drone and over all volume but it's still a bit loud.

In summary, you'll be disappointed by adding just a resonator. Add 400 cell cat, it won't affect flow at all.

Well I already paid a ton to have two 200 cel cats put on and I don't think it even helped with sound . Manga flow makes a dual 2 in and 2 out single muffler maybe I should try . It would be a center muffler . Would probably have to get rid of resonators and put it in the same area. I've heard on some systems the resonators make the exhaust louder .

I test drove a black with headers and wow it was so loud. Sounded like a race car while driving 40mph.

As C3Duece pointed out with the 400 cell count cat, it would be the only other option if you don't want to replace the LTH or replace resonators. The LTH are providing much more exhaust flow and assuming the diameter is larger, will great more noise. The stock cats really do quite down the car but at the cost of exhaust flow and mid-higher end RPM HP. Changing the mufflers could help but creating more restriction for the sounds to be muffled again.

On my 1996 E60, I only replaced the cats and removed the resonator but left everything else stock. The exhaust had more growl and better higher end RPM performance. I didn't change the exhaust manifolds to headers which is why the sound levels remained manageable.

Hope that helps and good luck!

Has anyone ever opened up the mufflers on these cars ? I wonder if they are hollow . No packing . Wonder if they were hollow I could pack one with steel wool and be more muffled

Got to find a way to quiet this car down . Maybe I'll have some 400 cel cats put in instead of the 200 cel .

You got any vids of how your car sounds now? I had long tubes on my old c63, the car was SUPER loud on cold start and WOT, but normal driving was ok. Is your car still loud when driving normally? Which lth do you have btw?

They are either renntech or evosport. They were on the car when I got it from renntech . I know they did a ton of work to it including replacement head bolts . Just have to find a way to lower the volume it's NASCAR loud . Might have to put baffles in it .

How much quieter would 400 cell cats be then 200 cell cats