Hi
I posted similar question under Mercedes Sedans section but no one replied, so I thought I try the Diesel section.

I have a MB C Class W205 C250d of 2015. I like everything in my car, with Stage 1 remap it generates close to 250bhp. The only thing I would like to change is the exhaust sound, and maybe get some extra performance from that (not much I know).

I searched a lot of places and cannot find a performance exhaust system upgrade for diesel engine. I read they don't sound good, they are too complicated etc. I also read that removing the DPF would give a boost but it is illegal, and also a muffler may change the sound but not much.

One garage I took the car to have a look ( I told them I need a quad pipe two left two right) told me there is no space for that on my car because of the adblue tank!

All I really need is someone knowledgeable to share some reliable info

Can I upgrade the exhaust on my car to achieve a better sound, and possibly some performance enhancement
Do I need to change all the system, part ? just the muffler ?

Thank you all

I don't think you will find many if any MB owners who did such thing.
MB are tuned optimally from the factory, so any aftermarket tune will sacrifice some performance to gain in other.
Now new diesel technology with dpf and DEF is very precise instrument.
Any exhaust leak, or change will start lighting CEL and emission codes.
I had DPF delete on 1 car and removing DPF inserts did not change the sound, at least not to degree I can notice it.
If there is HP gain, again not to degree to make it noticeable.
I believe you have OM651 engine? Did you get it dynoed to record 250bhp ?