Dynamat use in fiberglass structure

[popeyesteve]

I have used Dynamat material to line all of the floors and behind-seat storage in my El Camino with good success in reducing road and especially exhaust noise. This is all sheet steel structure which has a tendency to drum or resonate, transferring noise, especially exhaust of into the interior. I have a supply of Dynamat which I can use in my Avanti floors before I install my new carpet set, but I don't have any experience with it on fiberglass. Fiberglass may be a little more transparent to noise transmission, but I don't think it vibrates or resonates with the same intensity as steel which the Dynamat is primarily designed to dampen.

So, has anyone out there lined their entire floor (and maybe even the trunk) with Dynamat before and if so, are the results as far as sound deadening worth the cost and effort?

Steve

[Avanti83]

Simply put - Yes!

Mine is done with Fat Mat but it really helps. It doesn't help much with exhaust noise as that's by design.

Works well with heat also.

[plwindish]

I did my 76 with Fat Mat a couple of years ago. It does help reduce the road noise as well as insulating some heat coming back from the engine compartment.

[Silverplate]

I did my 64 Avanti with Dynamat last year before carpet and very pleased with results. Much quieter and the tunnel console area not nearly as warm...Mike

[Devildog]

I used exhaust wrap to reduce the heat in the cockpit on my Avanti. http://www.jegs.com/i/JEGS+Performance+Products/555/32075/10002/-1

Later I used insulation under the new carpet to lower noise, but the exhaust wrap alone significantly reduced the heat. With the wrap and insulation both, my inside temperatures are quite nice even in our 100 degree temps and near 100% Houston humidity, before A/C was not effective.

Joe

[BillyBob]

Looking to reduce heat in my '63. Are pre-cut kits available?

[brad]

I used Lizard Skin spray on heat barrier, over the sound deadener. Both inside and under the floors. I then used a dynamat type of foil backed sound deadener. Then over that I installed an extremely dense closed cell foam rubber, then the carpet. Needless to say the car was like a bank vault.

[CaffeineRacer]

I used Lizard Skin spray on heat barrier, over the sound deadener. Both inside and under the floors. I then used a dynamat type of foil backed sound deadener. Then over that I installed an extremely dense closed cell foam rubber, then the carpet. Needless to say the car was like a bank vault.

How well does that stuff hold up underneath the car (I assume that's what you meant by "under the floors")? Is it fairly durable?

[brad]

The heat barrier is like a ceramic slurry, and is a bit fragile. It will scrape and dent, but only in direct contact with something,but you won't rub it off. In other words, it does stay put, but It isn't tough like a bed liner urethane material.

The dynamat does not reduce sound penetration just resonance for the most part. That is what the dense foam is for.

Edited March 3, 2015 by brad

[PackardV8]

dynamat type of foil backed sound deadener. Then over that I installed an extremely dense closed cell foam rubber, then the carpet.

Wow! How thick was the total? Where did you source the foam?

jack vines

[brad]

The Lizard skin is about 3O-4O mils thick, and the foam was 1/2" Dynamat is probably less than 1/16" so about that total. The foam is called anti-fatigue mat, and was sold as a carpet underlayment...But, I haven't seen it for a year or so at the box stores.

[Avanti7]

Steve I'm about to do the same thing in my "70". I haven't decided on a product to help with the heat yet. Where did you get your carpet?

I

Is it a precut kit and did the pieces for the lower door panels come with it?

thanks, Jim

[popeyesteve]

Jim,

I got my carpet kit from Automotive Interiors & Accessories, Inc. (automotiveinteriors.com). I bought their interior and trunk kit together. They are cut, trimmed and sewn pieces and there are a LOT of them (including those door panel lowers), like the original factory installation. This is not a drop-in, molded carpet set like in a "modern" car. I am waiting for some warm weather before I start this project, my shop is not heated. I think that the Dynamat and carpets would also like some heat to make them more pliable during installation.

Good luck,

Steve

[Avanti7]

Thanks Steve. I've talk to Studebaker Int. and Auto-Mat, Inc. in Hicksville, NY about there kits and there are 14 pieces in there kits.

Jon Meyer told me he gets his kits from Auto-Mat. I will give Automotive Interiors & Accessories a call and price their kits.