Interior / Exterior / Audio Talk about interior and exterior mods including audio.

How much sound deadener for an FD?

Thread Tools
 
Search this Thread
 
Old May 22, 2010 | 03:21 PM
  #1  
NeverDieEasy's Avatar
Thread Starter
aka The BeasTT
Tenured Member 05 Years
iTrader: (5)
 
Joined: Sep 2008
Posts: 313
Likes: 1
From: Ft. Wayne, IN
How much sound deadener for an FD?

I'm going to sound deaden my entire FD, but before I place an order I want to see how much sound deadener you guys used. I plan on doing the entire floor, front to rear, as well as the doors. Thanks
Reply
Old May 26, 2010 | 10:43 AM
  #2  
muibubbles's Avatar
Bubblicious DEF.
Tenured Member: 15 Years
iTrader: (36)
 
Joined: May 2008
Posts: 4,273
Likes: 10
From: 732
what are you using? i used quiet coat (liquid) and used less than a gallon...
Reply
Old May 26, 2010 | 11:12 AM
  #3  
str8ryd's Avatar
Nearing Completion...
Tenured Member 15 Years
iTrader: (473)
 
Joined: Aug 2006
Posts: 4,736
Likes: 0
From: Chicago
What part of the doors did you coat? I'm going to be doing this very soon as well.
Reply
Old May 26, 2010 | 11:51 AM
  #4  
NeverDieEasy's Avatar
Thread Starter
aka The BeasTT
Tenured Member 05 Years
iTrader: (5)
 
Joined: Sep 2008
Posts: 313
Likes: 1
From: Ft. Wayne, IN
I'm using the normal mat style. Guys on norotors.com used 80-100 square feet for the floors doors and roof. I ordered 100 sq ft from fatmat.com. Heard nothing but great things about it and it was only $130 shipped
Reply
Old May 26, 2010 | 03:36 PM
  #5  
TwinCharged RX7's Avatar
Built Not Bought
Tenured Member: 15 Years
Top Answer: 1
iTrader: (14)
 
Joined: May 2008
Posts: 4,389
Likes: 964
From: Stamford, CT
I used 2 1/2 gallons of quiet car in my FD.

I coated about 90% of the inside of the door skin, and 100% of the interior portion of the door.
Reply
Old May 28, 2010 | 05:11 AM
  #6  
juicyjosh's Avatar
Seismic Disturbance
Tenured Member 15 Years
iTrader: (29)
 
Joined: Mar 2004
Posts: 612
Likes: 2
From: San Francisco
The sound deadening thread ^above^ has pics of the rear half of my FD covered with Dynamat. If I remember correctly, D. Hayes got kinda pissed for some reason(?). But I don't take stuff like that personally. As an installer and fellow forum member, I contributed what worked. The goal of my install was to reduce vehicle noise, which I accomplished.

I would hold off on deadening the ceiling. There's not much benefit in doing something like that.

Start with the front of the car's interior and make sure to apply the mat to cover the large punched holes in the metal kick panels which allow engine, road and wind noise to enter the cabin. I'd like to see someone try to use liquid anything patch that up .

The rest of my pics are self-explanatory. There's bigger pics in the West Forum "post pics of your ride" thread.

The amount you specified won't be enough if you're planning on doing the floor and the doors, but if you start from the front of the car, you can still drive the car and finish the trunk later. You may also consider one layer on the trunk separator - the big ~ 4' x 1' piece of plastic that separates the trunk from the cabin.

For ppl who undoubtedly will try to comment that that piece doesn't do anything, try driving your car with and without the separator in place. You don't need a dB meter to intuitively acknowledge that one layer on the trunkside of that piece would reap benefits as well.

When you're done with your project, be sure to post an honest objective result of your efforts, for example, "girls no longer get headaches from riding in my car..." or "I say what a lot less now."
Reply
Old May 28, 2010 | 10:01 AM
  #7  
purerx7's Avatar
Registered User
iTrader: (61)
 
Joined: Apr 2004
Posts: 7,334
Likes: 8
From: Los Angeles, CA
I can understand sound deadening the floor and doors, but what benefits does one gain when deadening the trunk?
Reply
Old May 28, 2010 | 10:17 AM
  #8  
GtiKyle's Avatar
Uncle Rico
Tenured Member: 15 Years
Community Builder
Community Favorite
Top Answer: 1
iTrader: (6)
 
Joined: Aug 2009
Posts: 1,537
Likes: 800
From: WA
The trunk area is a place for all the workings from the rear of the car to translate noise/vibration into the cabin. Think about the rear end, suspension, and tires back there. There's quite a bit of noise that comes from back there..
Reply
Old May 28, 2010 | 02:14 PM
  #9  
NeverDieEasy's Avatar
Thread Starter
aka The BeasTT
Tenured Member 05 Years
iTrader: (5)
 
Joined: Sep 2008
Posts: 313
Likes: 1
From: Ft. Wayne, IN
Originally Posted by juicyjosh
The sound deadening thread ^above^ has pics of the rear half of my FD covered with Dynamat. If I remember correctly, D. Hayes got kinda pissed for some reason(?). But I don't take stuff like that personally. As an installer and fellow forum member, I contributed what worked. The goal of my install was to reduce vehicle noise, which I accomplished.

I would hold off on deadening the ceiling. There's not much benefit in doing something like that.

Start with the front of the car's interior and make sure to apply the mat to cover the large punched holes in the metal kick panels which allow engine, road and wind noise to enter the cabin. I'd like to see someone try to use liquid anything patch that up .

The rest of my pics are self-explanatory. There's bigger pics in the West Forum "post pics of your ride" thread.

The amount you specified won't be enough if you're planning on doing the floor and the doors, but if you start from the front of the car, you can still drive the car and finish the trunk later. You may also consider one layer on the trunk separator - the big ~ 4' x 1' piece of plastic that separates the trunk from the cabin.

For ppl who undoubtedly will try to comment that that piece doesn't do anything, try driving your car with and without the separator in place. You don't need a dB meter to intuitively acknowledge that one layer on the trunkside of that piece would reap benefits as well.

When you're done with your project, be sure to post an honest objective result of your efforts, for example, "girls no longer get headaches from riding in my car..." or "I say what a lot less now."
Thanks for the info! I stopped reading the stickied thread above since all the pics people were refering to were no longer there, I'll have to go through it again. I've read several cases where people did the roof and noticed a huge reduction in wind noise, figured I'd give it a shot. I would give a before and after comparison except I bought the car as a roller so I have no idea what it sounded like.

Originally Posted by purerx7
I can understand sound deadening the floor and doors, but what benefits does one gain when deadening the trunk?
Originally Posted by GtiKyle
The trunk area is a place for all the workings from the rear of the car to translate noise/vibration into the cabin. Think about the rear end, suspension, and tires back there. There's quite a bit of noise that comes from back there..
Plus the fuel pumps. Also, the spare tire well acts as a reverb chamber
Reply
Old May 29, 2010 | 03:43 PM
  #10  
Black Magic's Avatar
2355lbs...
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2003
Posts: 1,420
Likes: 0
From: Santa Clara CA
****, i coulda saved all my OEM deadening and sold it to you when i scraped it all off!
Reply
Old May 30, 2010 | 09:02 AM
  #11  
David Hayes's Avatar
Lives on the Forum
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (6)
 
Joined: Jun 2002
Posts: 6,510
Likes: 188
From: FL
Originally Posted by juicyjosh
The sound deadening thread ^above^ has pics of the rear half of my FD covered with Dynamat. If I remember correctly, D. Hayes got kinda pissed for some reason(?)
I didn't get pissed I just pointed out factually incorrect information you posted about Quiet Coat.

Regarding why to do the trunk, any surface that can transmit vibration is an area that can benefit from sound dampening so that means the entire interior surface of the car, including the trunk. I posted up a thread on soundproofing my car with Quiet Coat with actual decibel reductions included:

https://www.rx7club.com/showthread.p...ght=quiet+coat

The trunk area yielded the least sound reduction, with a reduction of 1 to 3 decibels. Didn't know back then that 3 decibels was a 60% reduction in sound energy but you won't notice much reduction from doing the trunk.

Overall, I reduced noise by 13 decibels which is a huge gain. Here is a chart of each phase I did and the results:



Phase 1 was the trunk, phase 2 the doors, and phase 3 the underbody.
Reply
Old May 30, 2010 | 06:49 PM
  #12  
Black Magic's Avatar
2355lbs...
Tenured Member 10 Years
iTrader: (2)
 
Joined: Jan 2003
Posts: 1,420
Likes: 0
From: Santa Clara CA
Damn David, thats some hardcore TRUTH right there! Very badass!
Reply
Old May 31, 2010 | 08:00 AM
  #13  
David Hayes's Avatar
Lives on the Forum
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (6)
 
Joined: Jun 2002
Posts: 6,510
Likes: 188
From: FL
Originally Posted by Black Magic
Damn David, thats some hardcore TRUTH right there! Very badass!
Yes, the numbers don't lie
Reply
Old Jun 2, 2010 | 07:02 PM
  #14  
NeverDieEasy's Avatar
Thread Starter
aka The BeasTT
Tenured Member 05 Years
iTrader: (5)
 
Joined: Sep 2008
Posts: 313
Likes: 1
From: Ft. Wayne, IN
I would have used the liquid stuff on the interior but it doesn't deflect heat at all. The under coating that I used on the entire underside of the car has sound deadening material in it though
Reply
Old Jun 3, 2010 | 07:17 AM
  #15  
David Hayes's Avatar
Lives on the Forum
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (6)
 
Joined: Jun 2002
Posts: 6,510
Likes: 188
From: FL
Originally Posted by NeverDieEasy
I would have used the liquid stuff on the interior but it doesn't deflect heat at all. The under coating that I used on the entire underside of the car has sound deadening material in it though
A solution to this is to use the Quiet Coat on the interior and then to use some DEI heat shield over the under coating on the bottom of the car. Works well. And FYI - the undercoating spray on material is nothing like Quiet Coat so its sound deadening material will not perform anywhere close to the level of Quiet Coat which is from 6 - 20 decibels on the normal car. I was right in the middle of that range on mine, with a 13 decibel reduction.
Reply
Old Jun 4, 2010 | 02:02 PM
  #16  
NeverDieEasy's Avatar
Thread Starter
aka The BeasTT
Tenured Member 05 Years
iTrader: (5)
 
Joined: Sep 2008
Posts: 313
Likes: 1
From: Ft. Wayne, IN
I just ordered a gallon for the doors and if there's enough left, the roof. It wasn't the best option for what I wanted to accomplish on the firewall, dash, trans tunnel and floor boards
Reply
Old Jun 5, 2010 | 01:25 PM
  #17  
BryanDowns's Avatar
.
Tenured Member 20 Years
iTrader: (2)
 
Joined: Jul 2003
Posts: 1,175
Likes: 18
From: Louisville
fwiw, I bought 100sqft of Fatmat "Rattle trap" for my FD. Per their advertising, the rattle trap is like doing 3 layers of fatmat "extreme". I've never touched "extreme" so I cant verify.

Its a ton of work. I am around 14hrs or so into it. I have done the trunk, most of the floor, (Up to about the shifter, would have to remove carpet to go any further forward) and the doors. Its looking like I will have enough left to also do the roof.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Rbkouki
V-8 Powered RX-7's
0
Sep 29, 2015 08:54 PM
baix2
Power FC Forum
1
Sep 28, 2015 09:40 AM




All times are GMT -5. The time now is 10:24 PM.