Interior sound-deadening

[vtdds71]

As a 38-year-old sportscar, my '72 240Z is anything but quiet while driving. Some sounds are good (engine, exhaust), but others are not. I am particularly frustrated by the cacaphony of squeaks and rattles apparently caused by the rubbing of interior plastic/vinyl trim panels inside the car. Has anyone found a cure? Is there a product or technique out there that would somehow either (1) tighten the panels in place so they don't move around so much, or (2) sandwich between overlapping panels so they won't rub against one another and squeak? No, I'm not trying to create a Lexus here, just trying to eliminate extraneous noises that detract from the driving experience.

 

Also, how effective are the sound-deadening products that are adhesive-backed, or glued, under carpeting, door panels, etc.? Do they do anything other than add weight to the car?

[smoorenc]

I used "Lizard Skin" One bucket of the sound dampning and one bucket (2 gallons) of the ceramic heat/sound proofing" Came out really nice. Found out a lot of the nascar teams use it around here in NC. you can see pictures of it on my site. I would recomend it to you. Scott

[WiZZard]

As a 38-year-old sportscar, my '72 240Z is anything but quiet while driving. Some sounds are good (engine, exhaust), but others are not. I am particularly frustrated by the cacaphony of squeaks and rattles apparently caused by the rubbing of interior plastic/vinyl trim panels inside the car. Has anyone found a cure? Is there a product or technique out there that would somehow either (1) tighten the panels in place so they don't move around so much, or (2) sandwich between overlapping panels so they won't rub against one another and squeak? No, I'm not trying to create a Lexus here, just trying to eliminate extraneous noises that detract from the driving experience.

 

Also, how effective are the sound-deadening products that are adhesive-backed, or glued, under carpeting, door panels, etc.? Do they do anything other than add weight to the car?

 

 

I recently pulled the interior out of my 84 300ZX Turbo to improve the stereo system and to try to resolve many of the noise problems you mentioned.

 

I used the Dynamat sound deadening (stick on) material on all exposed metal surfaces after removing all interior panels and carpeting. I also applied 1/8" or 1/4" thick Felt carpet padding on door panels and under the carpets. You can use spray adhesive or good double backed carpet tape to apply the padding.

 

To address the squeeking panel problem try the following methods:

1.) Make sure all the panels are really clean before reassembly. Final clean mating panels with rubbing alcohol. A little dirt can make alot of

noise when rubbed together.

 

2.) Glossey surfaces have a tendency to stick together and squeek. Try some light sandpaper on the touching surfaces. This will cause the

surfaces to slide without squeeking.

 

3.) Saddle Soap. That's right. Saddle Soap. It is not just for leather cleaning. Soap never really dries out and will act as a lubricating film

between the surfaces.

 

It takes alot of work to cover all the interior surfaces to resolve noise problems. However it will be worth it. My 300Zx Turbo is as quiet (or better) than a new car. Other 300ZX owners are amazed at how quiet my car is and at how good the sound system is.

 

If I can be of more help e-mail me at: pcd_2000@yahoo.com.

 

Good Luck.

 

WiZZard

[GodZilla]

I have QuietCar/QuietCoat waiting to be installed. We'll see how it works out. http://www.quietcoat.com/

[smoorenc]

That looks a lot like the lizard skin stuff I used. Weighs a lot less than dynamat too. lizard skin soound and heat

[z-ya]

I used E-Dead sound deadening. One gallon did two coats on the entire interior (less roof) of a 240Z. Haven't driven it yet, but I hope it helps. It is much lighter than any of the sheet deadeners.

 

http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=53

[Icehound]

I used "Lizard Skin" One bucket of the sound dampning and one bucket (2 gallons) of the ceramic heat/sound proofing" Came out really nice. Found out a lot of the nascar teams use it around here in NC. you can see pictures of it on my site. I would recomend it to you. Scott

 

 

smoorenc, how much of the product did you end up using? -D

[smoorenc]

smoorenc, how much of the product did you end up using? -D

 

I used 2 buckets. One for heat (ceramic) and one for sound. You could just use 1 bucket (2 gallons) for the sound part. I had removed everything down to the metal, so I needed something for the heat against the firewall and floorboards. Remove all of the interior plastic panels and your seats and spay away. It is water based so it cleans up easily.

[GodZilla]

Here is a link to Quiet Car/Coat. It's a long read but the end result on his RX-7 is a reduction of 13 dBA in terms of noise. He used 3 thick coats which is the recommended amount and he figures he added about 40 lbs of weight to his car. I think he only did the trunk, doors, wheel wells, and hood. Firewall and under the carpet would give him even better results.

 

http://www.rx7club.com/showthread.php?threadid=195306

 

And another link at Z Car.

http://www.zcar.com/forums/read/1/723542

 

Other Info: Decibel (Loudness)

http://www.gcaudio.com/resources/howtos/loudness.html

 

Perceptions of Increases in Decibel Level (in our case, it would be a decrease)

Imperceptible Change: 1dB

Barely Perceptible Change: 3dB

Clearly Noticeable Change: 5dB

About Twice as Loud:10dB

About Four Times as Loud: 20dB

Edited March 30, 2010 by GodZilla

[TheMission]

I've used Raammat on show cars and other rides for sound deadoning and it's cheaper than Dynamat by far, while being just as good or better performing. It's heavy though, so if weight is a concern, the paint on stuff is ok enough. I still think the mat products are better in the end though, but Dynamat is way, way overpriced.

 

http://www.raamaudio.com/index.php?option=com_virtuemart&Itemid=60&vmcchk=1&Itemid=60

[TheMission]

Repost.

Edited April 20, 2010 by TheMission

[janaka]

I used eDead on my car (whole spare tire well, rear deck by compartments, front floors, doors) and I have to say that with my LS1 and a free flowing exhuast there is little difference. The car is just loud. Loud pipes save lives though as they say. In hindsight if I knew how loud my exhuast was going to be (did deadening before swap) I probably would have skipped the deadening. Now I'm looking at a cutout on top of it all My whole car shakes already, I can't wait to feel it with open dump under my ass.

[killaimdie]

 

This is a good idea for a cheap way to deaden sound.

[Nelsonian]

I used 2 buckets. One for heat (ceramic) and one for sound. You could just use 1 bucket (2 gallons) for the sound part. I had removed everything down to the metal, so I needed something for the heat against the firewall and floorboards. Remove all of the interior plastic panels and your seats and spay away. It is water based so it cleans up easily.

 

Smoorenc,

Just curious as to your first hand experience and results after installing this product and driving with it. I will have my car stripped down to bare metal as soon as it gets out of the fabrication phase and am very interested in this.

[wagon jon]

What I have done in the past is to take everything out of the interior of the car, including the passenger seat. Then start placing the panels back one at a time after either reupholstering the panel or making a new one. Dynamat works the best but it is a little pricey. Anything that absorbs sound, including carpet, makes a difference in sound deadening quality.

[Icehound]

I ended up using foam insulation from the local Boeing factory. Only time will tell how it holds-up...

[Nelsonian]

Smoorenc,

Just curious as to your first hand experience and results after installing this product and driving with it. I will have my car stripped down to bare metal as soon as it gets out of the fabrication phase and am very interested in this.

 

Any one else here ever use this product?

[Wedge]

I wonder how a stuff like lizard skin can stick to por15 I will probably have to sand it a little. That Boeing insulation looks awesome id use that over a base coat of lizard.

Edited March 7, 2012 by Wedge