custom exhaust for 560sec?

hello.
wuts the most cost effective way for this?
im hearing a regular exhaust shop, get rid of PRE-CATS and leave the regular cats so car will pass emission, then dynomax mufflers?

what is the ideal pipe diameter?

[BauhnBuster]

I put a cat back system on my 500E with a 3" diameter pipe and 2 mufflers. To tell you the truth, don't mess with the exhaust. The exhaust did not improve the car, just gave it some more rumble. At full throttle, I think I liked the stock 500E setup better. If you want to make some changes, go with the big guns where you will pay big price like Kleeman, Lorinser, Brabus, Eissmann, etc. I think Mercedes engineer their exhaust quite well. If you have an aftermarket forced induction, then maybe do the whole system IF the car needs it. The most common exhaust mod with the Benz is to remove the middle resonator to decrease weight and add some growl. Cheers!

Shaun