Sound Deaden

[lucid15]

So i have a bunch of Fatmat. I just got done applying it to the door itself only. Should i apply it to the plastic piece that is on the door as well, and the panel? Also, should i do the entire floorboard of the car? Im just trying to get rid of some road noise and make my 10" Type R, and my speakers sound as good as possible. Is it worth doing the entire floorboard?

 

[Defiant]

Any flat metal you can apply a deadener to will be the most effective. Formed shapes such as the floorpan will also help, but not as much. For the inside of the plastic panels, use Great Stuff urethane foam spray. Don't go wild with it, as it expands a lot as it cures.

Search "dynamat" on this site.

Interesting hint: high-level cars have been using expanding urethane inside the door pillars for years.

 

[97 GSX 97]

How easy is that foam spray to work with? Also how easy is it to shave some off if you have applied too much?

 

[phaseoneracing]

i've never used the foam for sound deadening. however it expands a lot , but it can be easily shaved later on with a razor blade or something. i like how dynamat works. just get it wherever you can and you should be fine. just make sure to get it on the panels you would think would move more than others.

 

[bmoha2]

works great for audio setups and for those of us that hate misc mysterious rattles etc. My friends civic had a killer audio system in it and he foamed every one of the interior panels that he could. A serrated kitchen knife works great to cut the foan once it hardens.

 

[romeen]

The expanding foam works well. But beware, it is very messy. Get it on your carpet, clothes, etc and it won't come off. It expands a lot more than you might think so use it with caution.

 

[bmoha2]

when I did the window rattle fix. I like how it turned out. Nice and quiet and I was very careful to kep it clean and neat.

 

[lucid15]

How much is this stuff? and where do i apply it to my panels? im curious

 

[95CarbonEclipse]

You can get "Great Stuff" expanding foam from Home Depot for about $5-6 per can. It works pretty good but is also pretty messy, as mentioned before. I used 3 cans when I undercoated my interior floorboard and trunk area. There isn't very many area's underneath the carpet that would benefit from the foam, but the trunk area has a ton of spots. Like I said, I used 3 cans, but I could have easily used 5 or 6. When looking for places to use the foam, look for open or hollow areas in the body that could be filled.

 

[lucid15]

SO since i already have fat mat i just used this to fill in the holes?

 

[95CarbonEclipse]

SO since i already have fat mat i just used this to fill in the holes?

If it's the actual mat, like Dynamat, then you'll want to adhere it any/all interior frame or body pieces. Focus on the thinner area's first since those will most likely generate the most noise. The idea is to try and make the inside of your car as rigid as possible. The use of a rubber-like coating is because sound waves don't bounce off of it as well as smooth, hard surfaces.

Imagine a giant pop can. This would represent your car. If you thickened up the thin walls, it would help deaden the sound. If you filled it up with foam, it would help even more. Get the picture?

In my car, it seems that the trunk area is especially noisy. I think this is due in part to not having a spare tire back there, but you may want to start there. The rear quarter panels are like huge, hollow, tin cans that seem to amplify any road noise there is while driving.

 

[97 GSX 97]

You can get "Great Stuff" expanding foam from Home Depot for about $5-6 per can. It works pretty good but is also pretty messy, as mentioned before. I used 3 cans when I undercoated my interior floorboard and trunk area. There isn't very many area's underneath the carpet that would benefit from the foam, but the trunk area has a ton of spots. Like I said, I used 3 cans, but I could have easily used 5 or 6. When looking for places to use the foam, look for open or hollow areas in the body that could be filled.

Did you do the inside of your door panels and such? I was also wondering if the large panels by the rearseat would benefit at all from the foam?

 

[bmoha2]

It did cut down the squeaks etc. I didn't do the inside of the rear side speaker panels. I couldn't figure out a way to do it without making a huge mess and it it a big area to cover. I hadn't noticed a lot of noise etc coming from that area. I spayed it on the backsides of the door panels with the door panel off the car. Let it expand and do it's thing overnight and then cut it to fit afterwards with a serrated knife. Be cautious and don't ram it in or force it into every little nook and cranny because as it expands it will find every little crack and come out the other side; the side you are going to see every day and cringe cause it looks like hell. I noticed that it bled thru the cracks the most around the edges of the big oval in the door panel. I might even suggest laying some seran wrap or sealing the cracks with silicon before doing it.

 

[lucid15]

SO by doing this it would greatly reduce the road noise within the car and grealty increase SQ? Also should i use the Fatmat adhesive rubber mats and stick them inside the trunk as well?

 

[95CarbonEclipse]

Did you do the inside of your door panels and such? I was also wondering if the large panels by the rearseat would benefit at all from the foam?

I didn't do any of the cabin area when I foamed my car. I was focusing on the trunk first because after rubberizing the entire floorboard and trunk area and painting all my interior pieces, I was ready to be done with the whole project.

I filled the dead space between both rear strut towers and the rear quarter panel, the hollow area that connects both of the rear strut towers, as well as the inside of each strut tower (I was sure to leave room for the removal of the struts when needed).

The entire process is messy and began to be a PITA. When filling larger spaces, you have to spray foam, then allow it to cure for a bit, and then go back and spray more foam on top of that in order to actually build up enough foam to fill the entire space. Does that make sense?

I do plan on spraying more foam but, at the time, I was just ready to get my car back together.

 

[Defiant]

Don't expect miraculous results. You're still going to be inside a cheap, unibody bell of a car. It'll help some, but it won't sound like an Infiniti.

 

[SwitchSkier]

I drive on the freeway a LOT at 75mph to go skiing in the winter, and the road noise gets annoying, so I wanted to make it a little better this year. I finished this a few weeks ago. I got 100sqft of Fatmat and went to town. I did the inside of the exterior of the doors, and the inside metal. Then all the floor, inside the rear quarter panels, and anywhere I could find.

Well I was going to post some pictures, but I can't actually find them right now. I'll go look and post some up.

And it definitely helped. The car just feels a lot more solid, not so tin-can-ish. It also really made my stock speakers sound a lot nicer.

 

[InfiniteGSX]

but it won't sound like an Infiniti.

+1... It wont sound like an Infiniti, It will sound BETTER! DSM's are great cars for quality audio. Perfect placement for tweeters, perfect placement for rear speakers and for bass, Hatchbacks always get better quality in sound and actual bass. My built system in my Accord, knocks pictures off my walls inside my house, gets me pulled over by at least 4 cops... But inside my Talon, it sends me to the hospital with respiratory problems.

The system I had in the Talon, Was only a small system. Niche CarbonFiber 6x9's in the back, Pioneer Components in the doors with Cerwin Vega 3" in the dash and a 12" Kicker Slim Sub in a custom built box for the AWD Trunk area. Nothing fancy. But it sounded 10000000000% better and Hit 100% harder then the competition full JL Audio system I built for my friend in his Mazda 3. A system he spent thousands on, and I didn't even break a grand.

All I have right now is my Trunk Dynomated up the ying yang. Gotta do my doors and rear quarter panels behind the rear speakers and it should be set for gold!

 

[Defiant]

Hell, if you're just going to cover the sound of the car with the stereo, why bother with a sports car?

Turn off the interference and do the sound test.