Dynamat and sound deadening

[bigchowder]

Hey all, I am going to be redoing the interior for my 510 2 door and I am planning on using Dynamat Extreme through the interior and Dynaliner in the firewall. Are there any suggestions on the best place to buy from, price-wise? Also, between the dynamat and the carpet - I have heard some people say they don't put any additional layers, and I have heard others say to us sleeping pads or aluminum flashing tape or other materials. Any thoughts? I know additional layers will help cut down on road noise, but I also know that thinner = better. A dumb question - aren't sleeping pads a bit thick to put under the carpet? And is it difficult to then lay out the carpet with the sleeping pads there? It's the first time I am going to be doing this, so I welcome any other suggestions or advice! Thanks to all who reply, I appreciate it.

[DISLEXICDIME]

rust proof the floor before you dynomat if you have not already .

[bigchowder]

rust proof the floor before you dynomat if you have not already .

 

Thanks. What is the best product to do this with?

[bigchowder]

Thanks. What is the best product to do this with?

 

 

Is Rustoleum a good product for this?

[datzenmike]

I used 'Torch-On' roofing bitumen. It comes in rolls about a meter wide with thin plastic skin to prevent sticking. It's dry to the touch and about 1/4"-3/8" thick, soft pliable and if warmed with a propane torch you can 'weld' seams. I snipped with metal shears, very easy and did not gum up shears. Pressed and molded over humps and bumps. Roofers warm with large torch and drop it on ridges and odd shapes and it shapes like a wet blanket. Best of all roofing companies tend to throw away short ends rather than join them. I got mine out of the dumpster for asking. A few sq yds did everything. Doesn't smell, dry not sticky and is quiet. Screw Dynomat and their expense.

[bigchowder]

I used 'Torch-On' roofing bitumen. It comes in rolls about a meter wide with thin plastic skin to prevent sticking. It's dry to the touch and about 1/4"-3/8" thick, soft pliable and if warmed with a propane torch you can 'weld' seams. I snipped with metal shears, very easy and did not gum up shears. Pressed and molded over humps and bumps. Roofers warm with large torch and drop it on ridges and odd shapes and it shapes like a wet blanket. Best of all roofing companies tend to throw away short ends rather than join them. I got mine out of the dumpster for asking. A few sq yds did everything. Doesn't smell, dry not sticky and is quiet. Screw Dynomat and their expense.

 

 

Thanks, Mike. I must admit that I am not a fan of Dynamat's pricing, and if that works just as well...maybe I will have to go that route. Did you find that the bitumen did a good job of shielding heat off the firewall, or did you use something else for that?

[elmerfudpucker]

I use Second Skin myself, I know the sales rep ;) as far as the sleeping pad, the dynamate roof paper ect is a vibration dampner, the pad would be a sound dampener, yes there is a difference and yes you need both. another thing that works is the fiber (not the foam!) under carpet pad for sound deadening. I pesonally dont like the roofing stuf due to the extra work involved and the need for that kind of heat in side the cab to get it to flex. And as stated earlier, treat all the rust first. A wire brush on a drill or grinder, then vac and wipe the dust out. The cleanner the surface the better the shit will stick. The quieter the cab becomes the louder you sounds will be! :D

[DISLEXICDIME]

i used por 15 on my last car i wire brushed cleaned really well with metal prep you have to rins very good after you use the metal prep

[RATDAT3]

After prepping the metal you can use "Metal" heat resistant ducting tape--its chrome looking and you can get it at the hardware store for way less than the cost of Dynamat. Regular auto carpet pad with this stuff works fine.

 

 

[Brian D]

Road noise reduction is something that I do for a living. There are many key things you can do to reduce road noise and be budget minded at the same time. There are areas in you car that will require more attention than others. Your floor is one of the areas that you will have to do the least amount of dampening to. Yes the floor does resonate noise but you will not have to use dynamat on that. The main objective in reducing road noise is understanding how it is produce. Each vehicle has a different resonace so each car will need to be treated differently. What you are doing by adding a product like dynamat is adding density to the panel. That will cause it not to move back and forth and it will change the frequency that it vibrates at which in turn will reduce road noise not cure it. The headliner and door are the nosiest areas in an car and can all be treated the same. When deadening the door do the outer skin then apply a full layer on the inside covering any large open hole. The roof is easy, sound deaden the apply a layer of jute pad over the top. Jute pad can be found at most automotive upholstery shops. You will need to use spray adhesive to make it stick. DO NOT USE INSIDE THE DOORS. It will get wet and mold. Next will be the floor. Add a layer of just jute pad to the floor. Continue this along with the sound deadening of the outer skin in the rear side panels if a car

 

 

[deadmonkey]

The stuff is called Butyl. For auto sound deadening they put foil backing on it and it is VERY sticky.

I bought a 50sq' roll on Ebay awhile back... haven't got a chance to put it in yet, but do a search for

"sound deadener" or deadening and will files hundreds of sellers.

The best deal I found was from a guy called Noise-killers.

 

the stuff for roofing uses the same Butyl but with tar and I think some fiber mesh of some kind, but is meant to be applied with a blow torch to heat it up and stick it to the roof. IMO, not a good application for an automobile, but I guess would work.

 

I wouldn't waste your money on Dynamat... it is overpriced.

[bigchowder]

Wow, lots of great advice here. Thanks, everyone. It will be my first crack at it, but I figure if I follow the advice I received from you all and take my time, I will do all right. Has anyone found that sound deadening their ride added too much weight?

[Laecaon]

Are you more worried about weight or sound? Is this a DD or a track car?

 

when applying the butyl stuff, I dont think it is necessary to cover an entire panel. What you are doing is adding weight to change its frequency that the panel vibrates. High density foam, like camping pads, actually kill sound.

 

On a side note. Has anyone ever noticed that German cars (VWs and Mercedes, mostly newer ones) smell like crayons? Supposedly it is the sound deadener that they use. My Jetta smells like it. Crayons has never been a bad scent, just unusual.

[bigchowder]

Are you more worried about weight or sound? Is this a DD or a track car?

 

when applying the butyl stuff, I dont think it is necessary to cover an entire panel. What you are doing is adding weight to change its frequency that the panel vibrates. High density foam, like camping pads, actually kill sound.

 

On a side note. Has anyone ever noticed that German cars (VWs and Mercedes, mostly newer ones) smell like crayons? Supposedly it is the sound deadener that they use. My Jetta smells like it. Crayons has never been a bad scent, just unusual.

It's not a track car, I am just going to be driving it for fun on the weekends and on fun runs. I wouldn't think that weight would be a huge issue, but someone told me to be careful or I will weight the car down too much with all the material added to the roof, floor, doors, trunk, firewall, etc. I don't want to slow it down too much, but I will have it running a KA engine so I am sure it will still get up and move. :)