Anbody use dynamat???

[astrohog]

Has anybody used dynamat in their Z restorations? I have never used Dynamat myself (not a big audiophile) but I have done some reading on sound-deadening cars and I would think that using a few small strips of dynamat here and there (door panels, c-pillars, inside back hatch) would really help the Z sound less "tinny" and rattly. Maybe this would detract from the "character" the Z's have for those of you who are truly Z purists. I would like to hear from you all (uh-oh, I just asked for opinions:) ) on what you feel about this, or if anyone has actually done it and if it made a difference or not.

Regards,

Astrohog

[hls30.com]

I have not used dynamat, but I have used several similar products as solutions to the issues of both sound and heat transmission. There are a multitude of insulation products available. I have used a good many including one of the most effective resonance reducers, sheet lead. If you search the archives here you will find information on several including Brown Bread, Dynamat, Aluminum faced jute, undercoating and conventional bedliner.

I want the interior of my car quiet and comfortable, to that end, I am using a "layered" approach to achieve acoustic and thermal isolation-that is to say a combination of several products and methodologies.

Will

[Ed]

A little off subject. But if you took your washing machine apart you will notice that the manufacturer installed a small strip of "sounddeadner" Dynamat type material on the sides to reduce noise. Now I installed sounddeadner all over the interior of my car, the roof, wheel wells anywhere I could. I would think that a few small strips can help. But is more better?

[Hrududu]

I used some in my car when I thought my speakers were rattling the panels. I have 2 4" audiobahns in there and was getting a buzz so i got some of that Dynamat and put it around the speakers and behind them. Unfortunately, the speakers themselves were the cause of the buzz, and not the panels. It did reduce some vibration sounds, but not all of em since most of it was the speakers.

[astrohog]

A little off subject. But if you took your washing machine apart you will notice that the manufacturer installed a small strip of "sounddeadner" Dynamat type material on the sides to reduce noise. Now I installed sounddeadner all over the interior of my car, the roof, wheel wells anywhere I could. I would think that a few small strips can help. But is more better?

I am no expert, but what I have found is that, technically, yes, more is better, but at a price. First off, Dynamat and its knock-off counterparts is expensive. Second, it is also heavy.

All the research i have done indicates that little strips (placed in a chevron pattern?) will help tremendously. I read somewhere that you could cover a relatively small percentage of the available area with the material and get 90 - 95% of the effect ov going crazy with it.

Disclaimer: I have no ACTUAL experience with this, but have done hours of reading in different audiophile and auto forums.

Regards,

Astrohog

[EScanlon]

There is a whole industry based on Sound Attenuation and Diffusion.

For my purposes, I wanted a car that was enjoyable to drive and didn't buffet me with tons of noise from the road, tires and it's own components. While ~some~ noise is to be expected, to me noise is an indicator of something not quite right.

I may have gone a bit far with my efforts, but the end result is that I can ride down the road with the original AM/FM radio playing and still enjoy a normal level conversation with the other person.

I used POR on the Floor Pans, the Firewall, and generally every piece of sheet metal I could see (with only a few exceptions) from the inside of the vehicle. From the exterior, I shot POR into the Cowl Bucket (all the way up into the windshield pillars and base), the complete front under fenders area, and literally poured it into the Hatch and rotated the hatch several times. I also shot POR with an air nozzle blower into the rear fenders trying to get it up as high as possible, and not skimping on it, so that it would coat down to the fender lips, it was also shot through the dog legs in front of the rear wheel humps. This alone provided a small level of reduction in the sound transmitted through the metal from vibrations.

That was step one.

Step two, involved Q-Pads, a tar sheet (essentially the same as what was oiginally on the car) manufactured by Evercoat (same manufacturers of a line of Bondo). Dynomat, Brown Bread and others may replace the tar with something else, and add other components to it, such as fiberglass, felt, foam, etc. but remember that you want to avoid anything that can soak up and hold water. The POR may be protecting the metal, but an ounce of prevention.....

The Q-Pads were laid down edge to edge all over the interior of the car: the floor pans, inside the doors, inside the rear fenders, the hatch, and over the access holes for the rocker panels and dog legs. Even inside the tool boxes. Generally if the other side of the metal faced the outside directly or even indirectly, it received the Q-Pad. In some instances, I cut individual pieces to fit in the "jigsaw" puzzle the floor pan became.

Then just the regular carpeting kit.

The results are significant enough that others who have ridden in the car have done the same with theirs. Then others who have seen what they've done..... There have been those that have modified / changed what I did and have even better results than what I did.

The thing to remember, is that if it's exposed steel, it WILL resonate and resonate means to give off sound. Then if you know it will be covered anyhow with something else, then go ahead and use a sound deadener on it.

The Washing Machine folks use a small amount to dampen the effect of a large piece of sheet metal with the vibrations of the internal mechanism. If you look at the inside of a dishwasher that's rated as being "quiet" you'll see not only the sound deadener but also some fiberglass fill. The Fiberglass provides both sound and heat insulation.

But lastly, regardless of what sound attenuation method you choose, make sure you protect the metal first. Otherwise, you'll have restored the conditions they set up at the factory which have caused us all a ton of grief.

2¢

Enrique

[Jackhammer]

I generally concur with Enrique. I have included several pics of what I did...which follows Enrique's procedures fairly close. The exception being in addition to POR 15...I sprayed in a coating of Dupli-Color Bed liner.

In addition before the interior goes in... I will be laying in a 5/8's" sound deadening fiber pad with foil on both sides thru-out...floor boards, firewall, sides and doors.

Some may consider it over kill ...but I consider it prudent measures to quiet down the interior noise that will be present with a 400+HP small block Chevy V8 rumbling under the hood.

Something I noticed is where the mat is installed the tinny sound is more of a thump sound. IMO I would put it in as many areas as you can. I used about 100sq.ft. of R-Blox.

Below are shots of my process.

http://www.classiczcars.com/photopost/data/503/medium/POR_15_Process_3-12-05_047.jpg

http://www.classiczcars.com/photopost/data/500/medium/PDR_1641.JPG

http://www.classiczcars.com/photopost/data/500/medium/PDR_1649.JPG

[vercingetorix]

I used some dyna-mat type stuff in my wifes Karman Ghia but the price was offensive, So in my Z I used three layers of Peel N Seal metal faced roofing matreal because it is locally available and less than half the price of other dampners but basicly the same thing, and then a layer of Luxury Liner from Second Skin Audio on the fire wall and transmission tunnel. The sound difference is amazing. After just doing the inside of the driver side door the road noise was cut by about 30%. All I need to do now is put Luxury Liner on the floor and rear deck and I'm done.

Best,

H Houghton

[CG Mojo]

I recently refurbished the entire enterior of my '71 using products from B-quiet http://www.b-quiet.com/index.html. It has about 80% of the performance of Dynamat at half the cost. I stripped the interior, photo documented it's rust-free condition, and then with stem to stern, sill to sill with peel-and-stick B-Quiet Ultimate sound deadener. Then came B-quiet Vcomp composite noise barrier on deck and floors. The new carpet. It makes a world of difference, added about 60 lbs, mostly aft, and cost about $300.