After installing my Koni's I've been driving around without most of the inner trunk liner.
And it seems to me it made the car a bit louder.
Plus I could hear my 4.57's very, very well.

So I did this:


When I tapped that panel under the spare it sounded like an empty drum !
Now it sounds like a half full drum
The "panel padding" is cork, leftover gasket from work.

Put all the liners back in and went for a drive.
Yes.. it is a bit better.
The 4.57's noise doesn't bounce around the trunk anymore.

 

I put sound insulation in my car too, only a little more extreme!

 

I also put dynamat in my trunk, passenger area and doors. Makes a big difference.

 

I'm going to do that one day. Trouble is I'm a professional procrastinator.