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I know that some of the sound deadening products are pricey (and Opel people love to save money)but earlier today I was using some plastic roofing cement (which was $6 per gallon) and thought that using this product with some heavy roofing paper may be a great way to deaden doors, floor pans etc. Anybody ever try this ???????????
 

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Opeler
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seems like it would be heavy, but I don't know how well it would work... let us know what you find out.

What do you think of self-expanding foam? (like 'great stuff') I used this once in the door of an old Honda just to take the annoying chincy sound out of the door when it shut, which seemed to work OK. I didn't notice much change in the road noise though, but I really didn't do much before and after comparison...

I have heard of people using bed liner on the underbody - to rustproof, protect, and deaden sound, but I don't think this is exactly a cheap option.
 

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I tried it on a an old Ford Galaxy and had to scrape off every last trace as the smell in the car was unbearable not to mention it would melt/ soften in the sumer and felt like jelly under the carpets. Need I say in time it started comming up through the carpets... What has worked for me is the dense thin carpet underlay foam that is easy to use and cuts easly .
 

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tomking
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Being in the roofing manufacturing industry for many years I can tell you that the automobile industry used asphalt saturated felts for many years as sound deadening material, so did washing machine and refrigerator manufacturers. Today it is mostly foam or polyester felts.
 

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Couldn't you use carpet underlayment? The padding varies in thickness, and could be cut to fit, then spray adhesive used to hold it in place. Most carpet places will have leftovers that they sell real cheap. This was what I had planned on doing on my next Gt after the floorboards etc were painted with POR-15. Jarrell
 

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70's Opeler, back 4 more!
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I've used Truck bed liner paint and some 3M sound deadening pads in key areas to quiet the sound coming out of the rear.

The pads do tend to get expensive.

Rally Bob had some good comments in another thread on the weight to sound deadening ratio. The more sound deadening you have, the slower the throttle response time to get that extra weight moving.
 

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OPEL-LESS!!!
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when dad did his 66 impala ragtop this summer, he put new floor pans in it, and put "herculiner" on the floor and trunk pan, took the trunklid off, and put the top down and let it bake in the sun, dried hard and you can't smell it when you drive it, worked good, but it is costly as somebody already said.
 

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Sound and heat

I think there are two issues to deal with when dealing with carpet replacement, at least in my mind. Besides the obvious problem of sound deadening, I would think that you would want something like a "foil lined" under carpet pad that would "reflect" the heat from the transmission tunnel. I know that the transmission tunnel can get real hot, especially in the summer. I've had a couple of GT's that would get very hot...
 

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By far the best reduction in sound I noticed was installing a Dynamat high end door kit. Due to the hollow structure of a car doors, they resonates much like the body of an acoustic guitar. I installed the door kit and was just amazed at the reduction in interior noise. I can now cruise on the highway and have a conversation with the passanger, INSTEAD OF HAVING TO SHOUT LIKE BEFORE. Installing the kit was pretty easy and you can take the slack out of those loose window cables while you're there. Done right visually you don't even know it's there.

Before I did the doors I put in a new carpet kit. I bought heavy felt at Home Depot, cut peices and glued it in with spray adhesive. Then glued the carpet peices on top of the felt. This did help reduce sound somewhat, but adding the Dynamat door kit really make the difference. May not be cheap, but in my opinion it did work. Just my two cents.
 

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Where did you find the door kit and what all is involved in doing the job right?
 

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The best price I found was at:
http://www.sounddomain.com/sku/DYN10435

Installing the kit is pretty easy. One side is foil, the other side has a peel off liner that exposes a super sticky adhesive. I removed each door panel. Used the panel as a template to figure out how to make the pattern needed for each door. Cut the Dynamat with a utility knife or tin snips. Cleaned up each door removing any old adhesive that would interfere with the Dynamat laying flat and sticking. Wiped it all down with denatured alcohol so I'd be sure the Dynamat bonds well.

Next is basically peel, place and stick the precut Dynamat peices on the door. Use any make shift roller (wallpaper roller, even a bedframe wheel) to press the Dynamat down to get a good bond. Use a knife to make cut outs for door handles and window cranks. Re-install the door panel. It's really pretty easy.

While you have the door panels off you will find two things that might need attention:

1) The cables on the window roll ups. Fix them now since the access hole will be covered with the Dynamat.

2) These stupid little metal tabs that clip onto the door panel and go into the plastic lined holes in the door. Where these clips mount on the cardboard door panel will be broken out in a few places. I fixed mine with some white glue the night before I did the door panel re-install. My door panels actually fit better now.

A rather simple installation that dosen't cost too much, adds little weight but makes a big difference in reducing interior sound levels.
 

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Sound Deadening

I picked up a couple yards of the thickest carpet pad (felt) at Home Depot similar to Jimsky. A good spray adhesive was used on the floor pans, then used again to anchor the new carpet to the pad. The thick pad makes the carpet feel plush underfoot. I did have to thin the pad down around the gas pedal to allow it full range of motion.

Also, I added the carpet pad to the hollow area below the Luggage Platform behind the seats, and I added it to the areas containing the gas tank, spare tire, and jack. I wrapped the jack & tool in cloth so there is no metal-to-metal contact, wrapped that metal hold-down bar for the spare tire, and stuffed my emergency tool box (old ammo box) with cloth to eliminate rattling.

Everything behind the Dash is anchored down tight, and metal-to-metal surfaces are coated with ??? (help me out here guys, its that gummy kind of glue we all used in school - comes in a jar - cap has a built-in brush). Anyway, some sort of a light adhesive to coat metal surfaces so they don't vibrate.

I like the Dynamat idea and am going to try it for the doors.

My doors sound like the cheapest rattle-trap. Its embarrassing. What have you all done besides tighten the wires? Window Guides? Seals? ????
 

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I found my drivers door had a broken lower window glass guide bracket when I did the Dynamat. When ever I closed the door it sounded so bad, the cheap buzzzzzz sound, it drove me nuts.

I don't have welding equipment, and it was impossible to get in there to drill for nuts & bolts.... so I made an aluminum support bracket and used JB Weld. This removed the buzzz sound for a few months until the JB Weld let loose. I finally just bent the broken bracket out of the way so it couldn't strike the door sheetmetal. Nice solid sounding door closes again...a deep stacatto thud now with the bracket fixed and the Dynamat installed.
 

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Opeler
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Has anyone tried this stuff? It claims to be 40% lighter, and it costs less than dynamat.

http://www.audio-n-more.com/sound_dampening.shtml

I was looking at the dynamat at best buy, but did not buy it because it was too heavy to carry to the cash register without a cart, and seemed like way too much money for what you get.


I was thinking of ordering some of this lighter stuff and giving it a try.
 

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Anyone tried this as underlayment?

We have a couple of boxes of a green hardwood/pergo type underlayment at work, each roll is 36 inches by 35 feet. It is a rubber like material and is used as a sound proofing in flooring. I think I would also use it in the doors. Anyone think this would work?
 

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Bo Know's '69's
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I just tried something different myself that i have yet to prove. I went to Home Depot and found some insulation used for drop ceilings. It is about 1/2 inch thick and has a bumpy layer of plastic which just peels right off. It's stiff enough to cut and piece together using 3M spray adhesive. I sprayed the under of the car with undercoating and used the undercoating on the floor under the isulation. Over that i put the carpet. It is soft and springs back after pressing my heel on the floorboard pretty hard several times. I used it to make my kick panels in the front and back and will cover it with vinyl material that matches my seats. I have not installed the panels yet but i plan on using sheet metal screws first then glue the vinyl to the panels. Pictures to come later. I will get a picture of the foam panel and post it soon. It was only about $4.00 for a 3 x 4 foot sheet and i used 6 sheets even did the cargo floor panel and the back deck panel.

Bo
 

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No....its not a Buick....
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I was a roofer for years as well, dont use that cement. its nasty stuff that will end up EVERYWHERE!!!!! Its difficult to get off things you dont want it on and stinks to high heaven a very long time. Also, its rather flammable!! I would go with somthing that was designed for the job. It may cost alot more, but you will regret using the roof cement. Just terrible stuff!
Joe
 

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Kick a little asphalt
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A word of caution against using expanding foam like Great Stuff etc. When I worked in a restoration shop, we had a guy bring the doors off his all steel nostalgic street rod into us for some final prep work prior to painting. He too wanted to get rid of the "tinny" sound when the doors closed so he sprayed Great Stuff inside of the doors. The expansion of the foam absolutely ruined a perfect set of very difficult to find doors. It warped the skins so badly and almost separated the skins from the frames due to hydraulic pressure that they were worthless. We had to cut and dig all of the foam out of the doors and spend hours shrinking the metal back into shape and re spot welding them back together. Needless to say, the $3.99 cans of foam ended up costing him more than you would care to think about. Besides the expansion problem, it also clogs the drain holes and traps condensation accellerating rusting of the panels.

Duane
 

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Opeler
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I found something to deaden the sound in my car. It seems just like Dynamat but its WAY cheaper. Its called flashband from Andek and it comes up to 6 inch wide rolls. I used one roll and covered the entire floor of my car and it barely makes a sound when I thump it now. Here is a link http://www.andek.com/H FLASHBBAND.htm
 
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