[JDRacer]

The existing sound setup is a weak point of F34 and not only. So the conversion of the sound setup was a mature decision. We started by covering the front doors with Dynamat and acoustic foam. After that we continued with installation of bigger pair of subwoofers 8" from Earthquake, followed by Twitter (basic had no Twitter at all, so Twitter panel was ordered separately) and mids from Focal IS100L charged and loaded with R2-500X4 Prime from Rockford Fosgate.

[Billfitz]

Nice, but FWIW most road noise is low frequency noise. Foam has no effect on low frequency noise, it lacks the necessary mass. Butyl is the right material for the job. I lined all my doors and for that matter any interior trim panels that I had to remove for one reason or another. An example material: https://www.amazon.com/Siless-mil-sq...6187c569a&th=1

[JDRacer]

Of course, door covered with Dynamat and above acoustic foam , so it work in pair to reduce vibration and road noise.

[Billfitz]

Yes, I get it, but the intent of that convoluted foam is to line speaker cabinets, where it absorbs midrange and high frequency reflections. It has no effect below 500Hz, while road noise lies below 200Hz.

[WingWong34]

These days I realise I'm getting old.. I used to fit stereos in cars - but only because the factory fitted ones where pants. I'm pretty happy with the Hk unit in my F34.. connected to a Sony walkman its great. I think the set of all weather mats help with road noise. I Can't wait to fit some 18" non runflats.

[Billfitz]

The mats can't hurt, as they have high mass. I noticed that the floor liners under the carpets of the F34 are particularly thick, which also helps. I've seen pictures of other F3*-F4* variations where the liners were thinner. Cars with thin liners under the carpets benefit from adding butyl to the floor under the liners. Based on how thick the F34 liners are I didn't bother adding it to mine.

[johnung]

Originally Posted by WingWong34

These days I realise I'm getting old.. I used to fit stereos in cars - but only because the factory fitted ones where pants. I'm pretty happy with the Hk unit in my F34.. connected to a Sony walkman its great. I think the set of all weather mats help with road noise. I Can't wait to fit some 18" non runflats.

If your car has a square set of 225/45-18 runflats, when you upgrade to non-runflat tires you can also upgrade the tire size for better comfort, stability and handling. 235/45-18 and 245/40-18 both work well on stock 18x8.0” wheels.

If you ever go to the expense of upgrading wheels to 18x8.5” or 18x9, a 255/40-18 is a perfect size.

You will notice the harshness of the stock suspension drop in half when you get rid of runflats. Much smoother over rough roads and potholes.

[WingWong34]

Yeah was browsing 235 45s .. but need to source 5 wheels.. would like 397s painted not cut.. would really like 398s but they're tricky to get in 4off 8j18s let alone 5off. 396s are OK..