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Minus000 · Joined: 29 May 2003 Posts: 363 Location: Sidney, B.C.

Road noise has been a real hassel in my car. In 4th gear its just noisy crusing down the highway. My engine isn't perfectly quite and my exhaust needs work but its still loud enough you almost have to yell to talk to the passengers. Looking at my front carpeting today and thinking about how much work my carpetting kit will be to get in place I noticed that there is no soundproofing under the seats and front pedal area on driver and passenger sides. I belive there should be some there. Are there aftermarket options for floor sound proofing? Should there be sound proofing there from factory? Right now the carpet is just sitting atop the sheet metal. I am also missing my hood insulation but as I understand this will not affect engine noise very much.

Mikri184 · Joined: 12 Sep 2003 Posts: 746 Location: Ferndale, WA

I have seen alot of differen things used under carpets, to aid in this. I think originally there was some sound proofing in there. But often times is removed becuase of water damamge or what have you, it doesn't seem to dry out like carpet and can cause a pretty good oder.
Some options I would suggest
1 Dyno mat like used in stereo installations. But quite pricy
2 J.C. Whitney sells a sound proof insulation, that works good and is fairly reasonably priced $25 for a good size roll. Two rolls will do the whole car.
3 I have seen used a lead filled sound barrier. Seems to work great but not sure how much or where to get it.
Other items I have seen but wouldn't recommend.
Cardboard, other carpet, Actually house carpet padding, insulation, Yes the house kind. Not bad ideas but I don't think where real good choices. Well hope this helps, Good luck!

Sleykin · Posted: Sun Sep 21, 2003 11:17 am Post subject:

I heard about folk using some type of roll roofing insulation stuff they use on mobile homes. I understand it is high density foam type stuff and really good for insulating and sound deadning in autos. I was told home depot sells it but there isn't one around here and I have not found it yet. I want to use it in my Bronco on the floor and behind the speakers. It is supposed to be self adhesive on the back side.
_________________
Glenn Neff
Medford, OR
87' 924S

porschetroy · Joined: 30 Dec 2002 Posts: 32 Location: Sacramento

Oh Yeah, there's soundproofing under there from the factory. It's heavy as hell! I've removed, and thrown as far as I could, the soundproofing mat under the carpet as well as the tar coating which is stuck to the sheet metal prior to painting the car. The mat alone was worth 7 lbs. for each quarter and the tar was 3.5 lbs each quarter. I won't even mention what the firewall pad, center hump tar, cargo area pad and tar would weigh. All told, I'd estimate there's over 100 lbs of insulation in our cars.

I don't even notice the road noise with the floor insulation gone. I just removed half of the firewall pad to weld some cracks and might get some engine noise now. If I get to the point that noise is an issue, I'm sure the lightweight jute-type roll insulation with foil backing will do a sufficient job and weigh almost nothing.