Any idea how much dyna mat people use to do the whole cabin? Anyone use something other then dynamat that was more cost effective?

The proper way would be to mimic the original tar paper. You don't need to coat the whole floor and rear wall.

The way dynamat controls sound is absorbing vibration and resonation.

If you're looking for actual sound insulating material check out something more like this
http://designengineering.com/under-carpet-...eadening-layer/

Check out Fat Mat and Noico for some good options.

Ben,
I did the entire cabin in the matting. Also did the door skins, and the cabin side of the firewall. I have a 2.7 with Weber’s. The insulation removed unwanted road noise, but still let’s me hear the beautiful exhaust note...

You were mating in your cabin? Hmmmm.....

After spending way too much time researching this, I'm going to go with Noico replacing just the areas of the original tar. Way less expensive than Dyna mat.

I also see peel and seal is something that folks use.

You should be able to take some quick measurements of the areas you need. I would do all the thin gauge steel areas in the cabin. Floors, firewall, doors, wheel arches.
Don’t use any asphault based material.

Thats interesting. If you go on lowes website and reviews peel and seal is extremly highly rated with the car guys and it is asphault based. They also noted that it doesnt smell in the cabin. I might buy some and see what its like. Only costs about 17 bucks for a 25 foot roll. Might be worth a shot..

Factory tar would have been ashpault based correct? I would think so.

Good luck finding objective information on the Intertubes. Ninety-nine percent of whats out there seems to be unsupported marketing hype, experiences from people who used product X with no objective comparison to other products, or armchair experts parroting what they've read from the other two categories. The best info I've been able to glean boils down to this:

Butyl vs Asphalt - the problems with asphalt-based products is that it melts at a lower temperature than butyl, and it stinks. Apparently it can fail when the car gets hot. Smell varies with product. It's also a lot less expensive than butyl so that's a big plus.

Constrained Layer Dampener - This is the big one for me. According to acoustic engineers, that layer of foil or other somewhat rigid material on top significantly enhances the sound dampening ability of the product by sandwiching the visco-elastic layer between two rigid materials. There's physics behind it, but I was convinced.

As for peel and seal, it is a free layer so will provide sound dampening, but supposedly not nearly as much as the foil-faced specialty products. I haven't found objective data about how much better though. Also, I've used peel and seal on roofs and the stuff stinks like hell. I don't trust anyone who says X doesn't stink. We just bought a new mattress that all the reviewers claimed didn't smell bad out of the box. It was a week before we could sleep on the damn thing without choking.

If I were going to go back in with a free layer asphalt product, I'd probably just buy the die cut tar kit from George . At least you'd know you were getting as good as factory. I'm hoping to improve sound deadening a bit with more modern products.

I think the peel and seal is foil backed according to what I read.. I might buy a little of each to see for myself.

I was in a car that had used peal and seal. On a hot day, it smelled like tar. There are dynamat copies that are lighter, cheaper and work fine. Amazon has good prices.

Noico, hushmat, fat mat are also options. Trying to figure what is really going to work best for me..

I dont want it to smell.

Come to think about it, I have a partial roll of the foil faced stuff on the garage shelf. I'd forgotten you can get it with or without.

I can't imagine it would be that expensive to set up some test panels to actually measure the sound attenuation of these different products. But darned if I can find anything like that. I hate having to sift through marketing hype.

I just found some Noico 50 sf for 60 bucks delivered.. I will start there and see how far it goes.

Covering every surface is a huge waste of material for minimal effect. The larger and flatter the panel, the more deadening you need. Also the thinner the metal the more you need. So the large areas of floor pan, the firewall, the inner fender wells, the inside of the door skins -- these are all great places to improve the sound. Covering the center tunnel, longitudinals, lower firewall box section -- these are already thicker metal, smaller sections (which increases rigidity) that don't need much/any sound deadening.

I use Damplifier Pro from Second Skin Audio

Come to think about it, I have a partial roll of the foil faced stuff on the garage shelf. I'd forgotten you can get it with or without.

I can't imagine it would be that expensive to set up some test panels to actually measure the sound attenuation of these different products. But darned if I can find anything like that. I hate having to sift through marketing hype.

If you want a very cheap but still good alternative, aluminum roof repair rolls they sell at Home Depot work well. Their like a 6”x25’ roll for 15-20$ i think

I chose nico branded material. 50 sf.. We will see what its like.

The peel n seal just is not worth the gamble.. I want to enjoy driving the car .. Not smelling ashpalt.

I used dynamat or the off brand substitute from Eastwood. I did a lot of the back wall and most of the floor. It seems more than adequate under the carpet. Did more than 5000 miles this summer.

I've gotten too krusty to post anymore about this stuff. Check my back posts if you want my positive experience with Peel N Seal.

I have samples of B-Quiet brand sound deadener and just compared it with some left over roofing peel and seal I have. The B-Quiet is thicker (1.32mm vs. 0.92mm) and the foil layer is much thicker and stiffer on the B-Quiet. The foil on the peel and seal is more of a foil mylar and very flexible whereas the B-Quiet has a heavy duty foil stiff enough to hold the shape of the whole sandwich when bent. Both of these characteristics (thickness and stiffness of constraining layer) would affect performance as a sound deadener from what I've been able to gather. The peel and seal I have is Cofair brand 'Tite Seal.' I don't know how much variation there is between roofing products.

I don't know what any of this means for real world results but since I had both products on hand to compare, figured I'd share.

When I did my research this is what I bought..

Still havent applied any but this is what I bought...

https://www.amazon.com/gp/product/B012AVX5H...=UTF8&psc=1