C63SEd1

It's at distal end of down pipes. Look at Post #82 on page 4 for pix.

Re-install is probably similar to removing it. Cut out the new piece of pipe and weld back the secondary cat.

Sanch

Exactly, but I don't see the point of ever putting it on again.

This is how the car should've come.

Aussie Zinga

My car is leased through my business with a buy back argument with the dealer in 2 years time as I will no doubt update the car with another? I'm wanting to do these little mods to my car but reluctant to as my dealer will notice when I put it in for a service. Anyway around this for you guys that are leasing your cars as well?

Sanch

I would avoid it if it's leased mate, just to be safe. Could potential void the lease agreement.

Davesc63

Or you just advertise it privately at the time and try to get more than the payout figure

Here's what is checked when you go to return the car:
https://www.mercedes-benz.com.au/con...t_Friendly.pdf

ruey220

after watching this video I decided I'm going to experiment with some custom setups before I spend on a tuner exhaust. I have some Borla XR1s on my ML63 and it turned out much better than spending a $5k Brabus exhaust for my car.

hopefully this puts in perspective some of us who are looking to tweak our exhaust systems for better sound or performance.

BriancEast

Can anyone confirm that a plasma cutter is required for this job? I went a local shop and left up. They told me they can't do it due to the angle of the cat, a plasma cutter can do it, but they just don't have the tool...

ruey220

I think if they use a sawzall the problem is it will cut some of the shield in the process because they cannot control it as it moves up and down. I had the same issue with my ML63.

PAKDADDY

whoever that did this. did your exhaust shop have to remove the cats to get the sawzall to cut the seconds?

Andyroo

A bit of an update on my non-perf exhaust experimentation: I had the rear boxes swapped out for a straight pipe, which made the sound a louder version of how it was before. Twice as loud I'd say, with a little drone (but not much). It didn't add any of the metallic growl of the cat removal, however, so I'm going to bite the bullet and have the standard rear boxes replaced and the secondary cats cut out, see how that sounds.

1 SIC DR

Hey Guys/Gals,

This is my 17 C63s coupe with the secondary cat delete. Love it even more now. Can't wait till my KW HAS kit and ADV.1 wheels arrive next week.....

Andyroo

Sounds great. How would you say the sound has changed in terms of volume and tone?

1 SIC DR

I drive all the time in Sport+, so a lot of more pops and gurgles, i would say 30-40percent more. Increased sound at idle.

This is how the car should have came from stock.

Happy with the exhaust now. Best bang for the buck...

Next on the list is drop, wheels and tune... Done....

Tvall13

Any issues with emissions inspection for this since the primary cats are still in place?

1 SIC DR

I haven't had any issues...

Vic55

Thanks for posting the vid... I figured this would be the gains (sound) that all have been wondering about and similar to my gains on the M157 resonator pulls Ive done in the past.

I recently had my car on the rack to do the diff oil change and noticed that the cats (secondaries) are up there against the OEM DP's. Did your shop have any trouble with the cutting and welding here? It looks like a it might take some time to remove the protective shield and then ensure no welding issues.

Andyroo

Sounds perfect!

1 SIC DR

No issues... Went to Eurocharge here in Toronto, Canada. Took about 3 hrs of labour in total. Stock secondary cats put in a box and can be re-installed if need be. One of the best bang for the bucks mods for W205...

Sanch

I agree, it's the best mod I think I've done... I get a lot of satisfaction out of it lol.

Looking forward to seeing the new wheels mate

PAKDADDY

Hello guys. Did you have to remove anything when the shop cut your secondaries. Like remove the cat or the shield? They can't get access to it because of the angle of the driver side cat.

skim7x

Can anyone tell me objectively -- is the sound after removing the second cat more "RASPY" than the stock sound? I love the tone of the stock sound, and don't want to give that up for raspiness just because it's louder... that's the only concern I have with doing the mod... would love to hear some confirmation, it's hard to tell on videos, for obvious reasons.

@1SICDR -- is that video pretty representative of how it sounds in person? Sounds great in the vid... nice and throaty...

1 SIC DR

Yep.. Sounds great... I like that its deeper and throaty. Just right...
I was going to go with AWE or AKRO exhaust but the AMG stock performance exhaust is great.

I think the secondary cat removal and stock performance exhaust is perfect. For someone who wants a little more deeper/throaty go with a cat less DP. I'm going to go down that route with a tune, in the near future

Dr. T

PAKDADDY

Man I guess no one knows

JacobsT

Sec. cats don't do much for emissions as far as I'm aware.


Not completely representative as there were other mods, but I had my resonance chambers removed and this in combination with the catless downpipes from supersprint. Relatively cheap but it's a bargain compared to a full Akra and it sounds WAY better.

Also no drone while driving unless you hit the throttle, then all hell breaks loose

1 SIC DR

Sounds great....

I did a secondary cat delete, video is above. What do you mean resonance chambers removed ? What was replaced in its place ?

Thanks

Dr. T