I’m looking at my options for carpet, with or without the OEM Jute, the OEM sound deadening/heat barrier and adding Dynomat.

For those of you who have applied Dynomat in the cabin.
When you install the carpet, do you apply the carpet directly to the Dynomat, or do you install the OEM sound deadening/heat material to the Dynomat and then install the carpet on top?

Do you purchase and install your carpet with the OEM Jute padding or without the Jute?

Is the Dynomat really any better than the OEM sound deadening/heat barrier material?
Thanks, Greg

 

For me, myself, personally... I treat the in-car dynomat as more of a sound deadener and forget about the insulation properties. I use it where there are large flat panels and places your feet touch and anywhere that adding bulk under the carpet is going to cause fitment / function issues
The reflectix type material is a better insulator so use that everywhere else (I try not to use it where your feet touch as it can flatten out and sometimes makes that crinkly noise)
Try to prevent the heat from getting into the car in the first place is better than trying to deal with in once it's in
Then I use jute backed carpet
my $.02
M

 

M...good points! My only problem with the jute---anywhere ther were 90 degree angles caused the jute
to bunch-up/lump-up. I had to remove jute in those 90 degree angles so the carpet would lay flat........
of course I had a layer of reflectixs taped to the bare floorboard. I will add another layer of reflectix and probably remove the rest of the jute from the carpet when I reinstall it.----but that's just me.

 

The space shuttle doesn't have the heat shielding on the inside..

 

A roll of 3m windo-weld ribbon sealer is a great way of dealing with carpet, sticks and holds carpet on inside corners and yet will let you remove it later if you need to
M

 

Thanks guys!

 

Space craft and satellites use 24k gold foil as an insulator.
Awesome stuff.
My Dad brought some home one time and we played around with in the kitchen.
You can’t bake a potato wrapped in it.
It’s not in my budget though.

 

pfffft, that's just parts of a crashed weather balloon. Nothing to see here (door bell rings and the men in the black suits are there...)
M

 

I put some good heat shield under the cabin and in the trans tunnel. I'm not a big fan of bubble wrap (Reflectix, etc) even though the previous owner of my '73 put it under the carpet. The actual insulation value is pretty low and it's usually overstated by manufacturers. It just adds too much thickness for what little r-value you get out of it. Get on Green Building Advisor's site or BuildingScience.com and see what the braniac building scientists think of it. Now, that said, the foil based bubble wrap does excel in one area which is reflecting radiant heat. Remember that heat is transferred in 3 ways: Radiation, Convection, and Conduction. Insulation (r-valve) blocks heat transfer due to conduction. Sealing air gaps blocks heat transfer due to convection (air movement in this case). Shiny foil surfaces block radiant heat. As said a few times already in this thread, the best place for insulation and a radiant barrier is on the outside of the cabin.

The Dynomat and similar products often come with a shiny foil side which acts as your radiant barrier. So they will stop some heat gain into the cabin and make it quieter as well. If I was the OP, I'd go with Dynomat or similar and put it down first, then add the OEM heat barrier at a minimum. If that's not enough, then add the self-adhesive insulation on the outside of the cabin under the floor. Something like this (they make it in both a self-adhesive version and a non-adhesive version:



DC

 

Thanks,
That is great information.
While the body is off the frame, I plan to add some type of heat barrier in the trans tunnel and under the cabin plus spraying those areas inside and out with spray on bed liner or similar material for added protection.

 

I just finished putting dynamat in my 69 Corvette. dynamat is mostly a sound deadener and not so much an insulator against heat. Dina sells a heat insulation material that you can use under the sound deafened. I did not use the jute and think it was easier to install the carpet and the quality was better.

 

While my transmission was out last year, I used the product I linked above in the non-adhesive version to fabricate a heat shield. I used the existing tunnel insulation clips and added a couple of extras. That foil is extra thick and I was able to use a rubber mallet to confirm the shield to the contours of the tunnel. It worked out very well. I think it is superior to any of the ready made tunnel heat shields available for our C3s.

I used the self-adhesive version years ago under the floor pans. Still stuck and stuck very well to this day. I think they helped a lot.

DC

 

Ahhhh- you should see the stuff I got from Roswell, NM- way better!!!




Totally agree- did my 73 with reflectix with some reduction-and is a good option if the car is not being totally taken apart. However in makes the seats/seatbelts a little to tight with the added thickness. The biggest difference was blocking both sides of my water heater- close one side and it just takes it a little longer to get boiling hot thanks to convection.

My 71 - I went with lizard skin inside-and rather than jute felt under the carpet - a thinner Heatshield product- as I have aftermarket seats and need the most room possible. The outside used the DEI adhesive backed aluminum shielded stuff and 3M foil tape to seal the seams

The exhaust pipes used "Federal Mogul Thermoflex Knitted exhaust sleeves" and inside of the sidepipe covers used DEI Reflect-a-gold.

You'll get a great education going to a junkyard and looking how M-B & BMW do their heat shielding in the cost no object cars.

 

Dynamat converts the movement of the vibration and turns it into silent low-grade thermal energy. No more noise = problem solved at source. High levels of noise develop in your vehicle due to impacts from the suspension and drivetrain. As the vehicle body vibrates, the vibrations move from one panel to another.

 

Exactly. I'll update if I can find it, but somewhere on this forum is a quote from Dynamat saying that you don't need to cover every surface for it to be effective.

I used Hushmat (basically the same butyl rubber sheets, but without paying the Dynamat, Go-Pro, Under-Armor, Nike-style premium). The 79 got full coverage, then Reflectrix. The 80 only got a few sheets on the large surfaces, and not even full coverage of those. And Reflectrix.

As others have pointed out, keeping the heat out is better than insulation, and insulation applied underneath the car also works. But the Hushmat seems to help with sound.

 

I was the distributor (southeast) for Dynomat in the early 90's.

We gave out thousands of service bell displays- every car stereo shop had one on their front counter. Marketing genius!!!
Just a small piece was all that was needed- look under the carpet of a BMW- just a small section is used on the metal floor. Otherwise added weight with point of diminishing returns.

STC- or Sound Transmission Class- fiberglass is slightly better than metal BUT worse for low frequencies. STC is measured in the midrange sounds. Tap your knuckle on a metal panel then on a fiberglass one. So what works great for one- might not be the ticket on the other.

Basics to absorbing sound- more mass (dynomat) - de-coupling panels( tough to do in a car)- Damping Compound ( Lizard skin and the likes)

New cars use a combination- like foam under the carpet (jute felt in the headliner)- dynomat type material - and a viscoelastic (undercoating)

Disclaimer-
Don't claim to be "the" expert ....just a few years under my belt of messing with cars and audio systems.

 

I used Damplifier Pro from Second Skin Audio. My research led me to two objectives with respect to this material. (1) I wanted to use a material that employed Butyl rubber as opposed to asphalt. Apparently the asphalt based material can emit quite a stink when hot. (2) I saw charts that suggested something close to 2mm thickness was significantly better that half that. (Damplifier is 1.25 mm thick, Damplifier Pro is 2mm thick.) The original carpet was glued to the fiberglass so prior to installing the Damplifier stuff I scraped all the glue off so all I had left was a smooth surface. The material came is squares. I don't recall the size but it was 12-15 inches square - something like that. I cut sections where needed so everything laid flat. I did the floorboards, tunnel sides, under the seats, under the rear storage area and even the sides and bottom of the rear storage compartments. I did not do the inside of the doors nor the T-Tops. I did not put any on the top of the tunnel. I think I double layered the floor boards but I don't really remember.

I then bought some duct insulation from Home Depot and covered much of the Damplifier stuff with a single layer. I don't remember exactly what the stuff was but it had adhesive on one side and foil on the other so installation was similar to what I had done with the Damplifier Pro. You would think this much insulation would cause a problem with the trim insulation but it didn't. In some places I brought the duct insulation up to the trim but not under it. I probably did the same with the Damplifier. It's all custom fit so you do whatever works.

I wasn't sure how well this was going to work so I elected to secure the carpet with strategically placed Velcro. The edges are all secured by the trim so we're talking primarily the floorboards and rear storage area. The whole affair has been in place for 8-10 years and I've had no problems with carpet movement, folds, etc. The noise and heat reduction was dramatic. Installation takes time so I know why GM didn't do it, but it really makes a difference. I recommend it for any C2 or C3. My C4 didn't seem to need it and I've never owned a C1 so I can't comment on that.

 

I used fatmat megamat (don’t know if it still exists) which is self adhesive butyl rubber with foil on it, Reflectix glued down with 3M spray adhesive, the stock jute, and then the old carpet and it all fit back in place.

also did the doors with sound deadener and the t-tops with sound deadener and relectix.

my point about the foil on the sound deadener is the foil is NOT to block heat, it actually radiates heat, like a heat sink. The vibration is converted to heat ( very little) since energy is converted, not eliminated. Conservation of energy is the term I believe. One form of energy converted to another form.

 

Yup!

https://www.sciencetimes.com/article...apping-guy.htm

 

I'll pile on here. DynaMat is a sound deadener. It adds mass and dampens/deadens sound vibrations. They also have a insulating material called DynaLiner which is a great product. You can get it in different thicknesses but I used 1/4". It's adhesive backed, so peel and stick. It's great stuff and holds up well. Use DynaMat on large panels in the center mostly to reduce vibration. Use DynaLiner everywhere you want to reduce heat transfer. It's light so no worries about adding a bunch of weight too. And I'm pretty sure it's a better insulator than the jute from the factory.


https://www.dynamat.com/products/dynaliner/