Anyone running their c63 with no cats??

[Liam29]

I just bought my c63 yesterday, already has the second cats out for straight pipes. I want bit more noise and power so thinking about getting primaries out then a tune.
How much more power?
Does it sound good or silly? Any drone?
Anyone down south who can do this?

Sorry for all the questions its my first german car so not sure who is best tuner

thank you

 

[flowrider]

You wont be able to remove the primary CAT's without making the car unroadworthy and failing the MOT.

 

[AMGeed]

You wont be able to remove the primary CAT's without making the car unroadworthy and failing the MOT.

Not quite true. How will it be unroadworthy? Unroadworthy implies the car has faults making it dangerous to drive.There are still plenty of places that aren't interested in counting cats when it comes to MOT time. If it passes the emissions test it will pass. Not saying every MOT station is like this but they exist. I'm not saying its legal either, just observation.
That said, removing the primary cats will bring on the CEL which has to be coded out. For that you will need Star.
MSL will certainly do the exhaust work and code out the CEL but that is in Birmingham. They will also remap the car to take account of the exhaust modification.

As a matter of interest, there are many cars out there with IPE/F1/Kleemann headers, no cats and the O2 sensors coded out. Not just Mercs. Currently they don't appear to have a problem with the MOT.

 

[flowrider]

Unroadworthy was maybe the wrong word to use but you get my point re the implications on future MOT's.

 

[clk320x]

Unroadworthy was maybe the wrong word to use but you get my point re the implications on future MOT's.

Well technically that’s the same with the secondary cat delete too

 

[Liam29]

Im more interested in the noise and power, i have had decats before on my Evo's.
I would rather do the resonator then mess around with primary cats anyway but, people have said they sound hollow and lose that signature amg sound.
Any help is appreciated.

 

[ShaunB]

There is nothing wrong with the sound of the standard C63. Get it remapped if you really need more power.
Personally I found my old C63 had more than enough power, and really struggled to transmit it to the road at times.

 

[Liam29]

I agree mate it sounds great just want it louder, it's not my daily so not too concerned with noise levels. I don't want to ruin it though and still want it perfectly drivable in comfort with no drone etc.
There's so many options, x pipe, h pipe, straight pipe so want to know whats the best set up if i chose to go the resonator route.

 

[Felstmiester]

Mines catless. Primary’s and secondary’s removed.

 

[Liam29]

Just both cats or resonator too?
Is it your daily, how much louder and quicker is it?

Mines catless. Primary’s and secondary’s removed.

 

[Felstmiester]

Just both cats or resonator too?
Is it your daily, how much louder and quicker is it?

its just both cats. It’s loud on cold start and loud when you put your foot down but not to different when ticking over or plodding around. No it’s not a daily. Always been a weekend drive. I’ve got a eurocharged map on mine and it produced some good figures on the dyno and some nice flames now it can breath.

 

[Liam29]

Was it mapped before the primaries mate or did you do it together? Im interested to see what sort of power increase you got from the decat alone.
I know it's not your daily but is there any drone on motorway or anything as its still my daily and i do a few miles on motorways everyday. And stuck in traffic im being told smell of exhaust fumes in cabin?
Thanks for the help bud

 

[Felstmiester]

I had it mapped the week I got it. Apart from the map it was standard. Secondary’s came out around a year later. 6 months after that it got booked in at torque flow at msl to have primary’s out and then on the dyno for a fresh eurocharged map. Like I say it was mapped previously but think it gained about 20bhp. Weather this was down to the new map or the fact it is now catless we don’t know but Jerry himself ( owner of eurocharged) sad it felt strong.

I would say you get a certain amount of drone on motorways yes. And yes fumes. If your sitting in traffic with windows down you sometimes get a whiff.

 

[Deleted member 37751]

I had Kleeman manifolds and secondary cats removed on my E55K and, although it did sound “better”, I could smell petrol whenever stationary, got tiresome pretty quickly.

 

[Liam29]

Cheers guys, i appreciate the help. Might just leave it how it is for now

 

[Dogbreath]

On my E55
Kleemann mids, Primary and secondary’s are gone, binned the resonator for a xpipe, changed the mahooooooosive rear boxes for power flow boxes, had rear Amg end pipes welded back on to look stock...... sounds like the devil himself... my weekend car so not bothered who it annoys, certainly doesn’t annoy me.... i love it

Lee

 

[John]

I had Kleeman manifolds and secondary cats removed on my E55K and, although it did sound “better”, I could smell petrol whenever stationary, got tiresome pretty quickly.

+1

I found it quite annoying after the novelty wore off.

I did consider fitting secondaries back somehow or buying sports CATs to solve but the car was running so well I didn't want to mess around with it.

So I put up with it but I don't miss it.

 

[John]

If I were ever going to modify and exhaust in future, I would consider shorty headers (although I am not sure they are worth bothering with), a X pipe, secondary CAT removal and leave it at that as you already have the "C63 back boxes" which were one of the preferred options on the E55.

 

[confusionhunter]

I have the secondary cats removed. I must say that the interior sound deadening really does disguise how loud it is outside, even with the windows open. Ive been outside when my GF is driving and its much louder than you think when driving.... which is in a way.... dissappointing! Maybe we should be ripping out sound deadening

Dogbreath, any vids of your car and exhaust sound?

Hi BTW.... long time lurker....