My first post here. I have to say that the 21 pages of knowledge and wisdom accumulated here is astounding.
I did a few mods that some may find a little extreme. ST XA coilovers (I had a good deal for new ones), 245/40 R19 Conti Sport Contact 7 tyres and Racechip GTS to name a few. All these led to levels of NVH that are honestly quite bad, esp on rough roads.
Now that I have expended all my budget on the above mods, I went on to DIY sound deaden/proof my FL 2020 Superb. Following the advice here, I have done:
1) Bonnet (2 layers)
2) Boot (2 layers)
3) B Pillar
4) Outside Wheel Arches/Fenders (2 layers)
5) Front Floor (partial 2 layers. i didn't want to take out the console or front seats)
6) Driver's Door (2 Layers)
About to do the other doors, wheel arch inside, roof lining and probably seat bench.
I can say (according to my butt dyno) that the car has about the similar comfort levels as my old(er) 2013 Audi A4, plus higher performance and a whole lot more boot space. Yes, even with coilovers, it's amazingly comfortable at factory settings. I'm stunned! I had never imagined that the sound deadening would actually settle the vibrations and road feel.
Can't wait to do the rest!