Datsun Roadster Forum-311s.org

I'm getting ready to add sound deadening material to my 68 2000. I'm curious as to whether anyone has strong opinions about the liquid paint on type versus the sheets of material like Dynamat?? Has anyone tried both and compared?

I used Lizard Skin in the in the 68 and Fat Mat in the 69.
Assuming you are starting with a clean dry base, both have their advantages.
The spray on Lizard skin goes quickly and fills well. If the body is stripped to the tub with all glass and rubber removed, I'd use it again. If the car is assembled to any degree, I'd use a Dynamat. I found it easier to put in the doors and used two thicknesses on the firewall.
Hard to say if one is quieter than the other (they are open cars).
The Dynamat may resist heat transfer a bit better.
If you have a buzz or rattle, its much easier to peel a d stick than mask, mix and spray.
Dan

I enjoy the Solex symphony, gearbox whine, and exhaust bark.

Wouldn’t muffle them for any reason.

YMMV.

We regularly do this to the roadsters that we restore-- some for sound deadening, but mostly for heat (especially on our turbo swaps):



A lot of our conversion that we do have catalytic converters, and we place those in the X, right under your seat, so that heat reflection really helps on these cars.

Here is another one:



It is labor intensive to install, but I find that it makes a dramatic improvement with our cars.

Michael

I'm using Hush Mat, no logo, black foil and less expensive. And after removing the original crap I would never use anything spray on or paint on.

I recently installed Kilmat (made in Russian Federation, FWIW), I hope it isn't radioactive or anything . I used it inside the doors, under the trunk lid, floor pans, trans tunnel, and firewall. I'm still wondering about what to use underneath the hood.
Even though it's an "open" car, it made a significant difference in rattle and vibration dampening. I would highly recommend sound deadener to anyone thinking about it.

rwmann wrote: Tue Jan 19, 2021 5:14 pm I enjoy the Solex symphony, gearbox whine, and exhaust bark.

Wouldn’t muffle them for any reason.

YMMV.

a
You actually hear all of these way better when you install soundproofing

I’ve never used spray on so no opinion but as Michael said one of the main reasons is heat insulation I would be surprised you get any with spray on
I used Kilmat and a leftover of Second Skin Damplifier ! both are butyl based so high quality and no smell
The Kilmat was pretty good for the price point but the Damplifier is a higher quality product and it showed, the leftover I had was 10-12 years old but it behaved as if it had been purchased last week

Pjackb wrote: Sat Jan 16, 2021 10:59 am Most of the first step of soundproofing is done , I still need to do the doors and a few place under the dash frame to quiet down the rattles
It should be out to the paint shop next week

I look at it as two distinctly different processes taking place. First is sound insulation, to reduce the passage of sound from where it is produced into the cockpit. This is primarily of course the firewall, but also the rear platform to stop rear tire and differential noise. Second is mass stuck firmly to sheet metal panels to limit their ability to vibrate and resonate. Obviously foam is best for simple sound insulation, but for me something with some mass is needed to prevent resonance. I used ice and water shield on the floor and on the lower firewall.

spriso wrote: Tue Jan 19, 2021 5:19 pm .....

It is labor intensive to install, but I find that it makes a dramatic improvement with our cars.

Michael

I'm finding this out the hard way. I'm only going up to the stock board on the firewall and what a pain to fit it all. This is my first time doing an interior and I don't like it.

I went through several revisions to get the door trim templates the way I want. You get one piece of vinyl per spot and if you mess that up then you'll be ordering bulk vinyl off the web to redo it.

Based on all the comments I think I'll go with the dynamat extreme. One question, on the dynamat website the bulk pack 9 sheets (18"x 32") sells for $340 but on other vendors sites (Summit Racing) a pack of 9 sheets sells for $195. Are these the same product?

C.Costine wrote: Wed Jan 20, 2021 8:17 am I look at it as two distinctly different processes taking place. First is sound insulation, to reduce the passage of sound from where it is produced into the cockpit. This is primarily of course the firewall, but also the rear platform to stop rear tire and differential noise. Second is mass stuck firmly to sheet metal panels to limit their ability to vibrate and resonate. Obviously foam is best for simple sound insulation, but for me something with some mass is needed to prevent resonance. I used ice and water shield on the floor and on the lower firewall.

Exactly this. Dynomat type products are great and do take care of part of the equation, but there's more to be had. Dynomat can be effective without full coverage too, chunks in just the center of large panels helps a ton with vibration.

I've used the ice shield before too, it works pretty good on a tight budget. I taped every seam and edge with foil tape for extra protection because I heard horror stories of it dripping when hot. From what I can tell they were just stories, it never got close to that soft even on the roof of a black truck in summer.

Pjackb wrote: Tue Jan 19, 2021 9:11 pm

rwmann wrote: Tue Jan 19, 2021 5:14 pm I enjoy the Solex symphony, gearbox whine, and exhaust bark.

Wouldn’t muffle them for any reason.

YMMV.

a
You actually hear all of these way better when you install soundproofing

Not when running without a top, which also moots the sound deadening.

YMMV

rwmann wrote: Wed Jan 20, 2021 12:26 pm

Pjackb wrote: Tue Jan 19, 2021 9:11 pm

rwmann wrote: Tue Jan 19, 2021 5:14 pm I enjoy the Solex symphony, gearbox whine, and exhaust bark.

Wouldn’t muffle them for any reason.

YMMV.

a
You actually hear all of these way better when you install soundproofing

Not when running without a top, which also moots the sound deadening.

YMMV

Yeah you need to ride in one

Hopefully we get to go at the Glenn this year I'll show you , Proof is in the pudding as they say

Hoping to do this in the next day or two. Using FatMax. Any installation tips to minimize bad words and excessive alcohol consumption?