[DM3]

I purchased a few sheets of Dynamat Xtreme and installed on the left-rear roof section to try it out.

Several people said that there are options not as expensive, anyone out there have any suggestions?

Thanks DM3

[many birds]

I used Noico. It seems to be a similar material as Dynamat, but cheaper. If you really want to quiet things down, you will need a thin layer of closed cell foam and mass loaded vinyl. Also you don’t need to Dynamat every square inch either. You may want to take a look at the Sound Deadener Showdown website—lots of good info there.

[Rocco Testa]

I was watching the TV show gears one day and they had a quick tip for a less expressive product then those sound mats. Dave from the show said to go down to your local home store and buy some boiler rap, he went on to say its just about the same thing but much less in price. The only difference is you with need to use some 3m adhesive and spray it on both parts to hold in down as it don;t come with the adhesive all ready on it. Well I did just that and have been using it ever since with no problems

[JLMounce]

Dynamat is a simple foil backed butyl rubber product. It's used in applications ranging from automotive to household. You can go down to your local home depot and pickup rolls of similar product. Dynamat just was the first to really market it for the aftermarket automotive world and their product is fairly easy to handle based on how it's packaged.

many birds alluded to it, but what you really want to do is known the why of the products used to control sound. That can help you make purchase decisions based on your needs and wants.

If you look at modern luxury automobiles, they use three basic products to control sound and dampen vibrations, typically called NVH (noise, vibration and harshness)

The first product is what's called a constrain layer. This is your dynamat type product. It's function is to add mass and prevent sympathetic vibration in large sheet panels that may be prone to such vibration. Depending on the panel, you may need more or less constrain layer. The larger and flatter the panel, the more you need. Panels with many creases and curves don't vibrate as much by nature, so you don't need as much constrain layer. Typically 50-70% panel coverage is all you need and just focus on the flat areas. Although if you want to cover 100% you can, if it makes you feel better.

The second layer is a decoupler. This is typically a woven fabric or composite material like jute. This is placed on top of the constrain layer and acts as insulation, cushioning for the driver to get them off the vibrating panels, a moisture wick and also has some sound knock-down properties. This layer is your money layer and where you really get the most bang for the buck. It's also typically the lightest material, so you can literally use it all over and not have to worry about added a lot of weight to the vehicle.

For most muscle car enthusiasts that don't want to create a numb feeling and sounding Cadillac, you can probably stop your sound treatment at this level. The car should retain a more solid feel, be more comfortable in hot and cold conditions and knock down the majority of the sounds you don't want to hear. You'll still hear the tires on the road, the exhausts drones and rumbles etc. Typically the kind of stuff most gearheads like to hear.

The final layer used is a mass loaded vinyl. This layer does the bulk of sound knock down and works on those errant sounds from the exhaust, tires, wind etc. If you want a very quiet ride, put this stuff anywhere you can, as thick as possible. The problem with this stuff is it's "mass loaded." It's heavy and for performance cars, that's bad. This is why I state many people will be pleased stopping before this stage. But used in key locations it can help further. Up around the firewall and around the wheel wells is a good place to add this. You're not adding a lot of weight by covering the entire car, but you are adding the material in places where most arrant noise comes from.

Then put your desired carpet on top of all of that. The carpet will also have some sound knock-down and decoupling properties, but very minimally.

So to recap: Dynamat type product first which helps with vibrations and thuds. Decoupling layer next which is your insulation layer to keep the car cool in the summer and warm in the winter. Mass loaded vinyl next for wind, tire and exhaust noise, then carpet to cover it all up.

For the constrain layer, the DEI undercarpet lite is a great product that doesn't break the bank. Noico is often used as well and is similarly priced.

One thing with classics to watch out for is going too thick on everything. Modern vehicles can have close to 3-4" of all this stuff before the carpet. The classics were never designed to allow that much material, so you want to stay a bit thinner, unless you're having custom carpet done that can deal with the added thickness.

[RocktimusPryme]

I used a mixture of Noico and the Summit branded stuff. I was more concerned about the longtubes melting my feet than I was with noise.

[DM3]

Thanks for the info guys!!

I was thinking covering as much of the interior as possible with the Dynamat Xtreme and then cover the roof, floor and firewall with an additional layer of some kind of insulation.

Also doing the inner skin of the door and the door panel.

[JLMounce]

Dynamat makes custom cut templates for the entire f-body, which takes out a lot of the guess work. To do the entire car, it ends up being about 1400, so it's not cheap. There's parts of that you can get away with not doing however. You don't need to do the trunk lid and the trunk pan itself is less of an issue, especially if you have the jute backed divider. If you're not running powerful speakers in the rear deck, you can also get away with not doing the package tray.

This also kind of goes for the doors. If you're not running speakers in them, you'll gain the most by making sure that they door weather strip is in good condition as well as the door card and the window felts. Most of the noise from the doors is coming from loose crud inside them, the window not being contained properly by the felts etc. Second Skin makes a good spray on constrain layer that is easier to work with should you wish to do the inside of the door and you can add a mat product under the card for more if you want.

It does kind of sound like you're going for a more cadillac type experience, so I would focus more on the decoupling layer and mass loaded vinyl layer in strategic places. You'd want to do the trunk as well in that situation.

This isn't part of the insulation package, but another area to address is the nuts and bolts of the car itself, literally. Spend an afternoon with the wrenches and sockets out and put a cinch on any nut/bolt you can find. A lot of NVH comes from stuff just not being completely tight and rattling around. You'd be surprised how much more solid the car feels after doing that.

[1969 Ram Air]

Go to home Depot and buy the foil backed hot water heater wrap. It's cheap and it works.

[DM3]

I am not going crazy, I will not be doing the trunk or trunk lid, not the hood.

Currently my car is completely stripped, so now is the time to do it.

[DM3]

This is the current state of my car....

[JLMounce]

Yeah if it's apart now is definitely the time to do it. What my personal suggestion would be based on not going crazy, would be the following.

Dynamat custom cut Floor and Roof kit
DEI undercarpet lite or Noico Sound deadaner (entirety of the floor and roof)
Trunk divider with jute backing
Jute package tray liner
Second Skin Luxury Liner Pro on the firewall and under the rear seats, over where the muffler/s will go. Target this area depending on if you're doing hanging mufflers below the floor pan, or the transverse muffler between the back of the floor pan and the axle.

Classic Industries has the best pricing I've found on the dynamat custom cut stuff. Right now the floor kit is about 90 bucks cheaper through them than through dynamat direct.

That's going to be cost effective and really help with vibration, heat/cold and sound control. I would hold off on the doors. They're so easy to do at any time that if you feel like you need the extra vibration and sound damping there, it can be added on a random saturday.

[amcmike]

Originally Posted by DM3

I am not going crazy, I will not be doing the trunk or trunk lid, not the hood.

Currently my car is completely stripped, so now is the time to do it.

I would probably at least put some on the inner wheel wells to knock down some road noise.

[Mike Davis]

I have tried a few different brands. I just did the inside cab area of my Toterhome. Road noise plus the diesel engine in the front was loud. I used 2 layers of Dynamat extreme on the floor, in the dog house and one layer inside the doors and another between the door and door panel.
Made a huge difference in the quietness in the cab.


Be careful of some of the ones from Home Improvement stores that have a tar like material in them. On a hot day your can smell it from 20ft away.

[70s_Restorer]

I just used Rattle Trap from Fatmat.com on a 68 Lemans convertible. It’s 80 mil thick. Very happy with material quality and price was very reasonable. Much less expensive than Dynamat. I bought it direct off their site with discount coupon and free shipping, less $$ than buying on Amazon.

[DM3]

I have been reading all your comments and too much online. I think I will just cover the inner area with one layer so I do not eliminate all the noises that go along with a muscle car, plus I do not want to add more weight.

Thanks for all the suggestions and experience,

[JLMounce]

That second layer, the decoupling layer you're going to want. Go lighter on the constrain layer if anything. That second layer is doing the brunt of the work you want done in keeping the car quiet and temperature controlled. It's also the lightest of the layers. The entirety of the passenger cabin, is going to be at or less than 20 lbs max. The mat products also aren't as heavy as you'd think, until you start going overboard with it, which again is not necessary unless you're trying to build a Bentley.

I would forgo the mass loaded vinyl, that's the heavy stuff. 50% coverage with a mat product and 100% coverage of something like the undercarpet lite or noico liner is going to be a pretty nice ride, and better than the car would have been brand new. I also suspect that it would be about the same, if not slightly lighter than the factory paper backed rubber underlayment that was used in these cars originally.

[DM3]

Great, thanks.

I don't want to add too much weight, I am building this car as a driver, but also to beat my buddies 455 73 vette who has been talking smack since I started this process.

I will post pics as I go along, hopefully it will help others as you have helped this amateur.

[DM3]

Finished first layer of Dynamat Xtreme on the roof.

Since where is still welding to be done on the firewall and floor panel, I will do the doors next.

[DM3]

I will put a second layer of DEI Undercarpet Lite over top of the dynamat on the roof and floors.

[DM3]

Ok, last question.......

I was thinking, if I use the Design Engineering 050113 Under Carpet Lite, it is not a self adhesive product.

So I started looking at Noico Green 170 mil Waterproof Sound Insulation, Heat and Cool Liner which is a self adhesive product or Dynamat 11102 Dynaliner 32" x 54" x 1/4" Thick Self-Adhesive Sound Deadener. Do these two work the same?
Looking to get the roof done before it leaves for the body shop hopefully next weekend.

Thanks

DM3