When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So a few things to note that were brought up in this topic that I figured i'd help clear up for current/future readers
For starters, please do yourself a favor and do not use cheap amazon sound deadening products. You will be cleaning melted butyl of your expensive car in the future.
Second, please don't bother with trying to absorb outside noise with acoustic foam. You're fighting an uphill battle in this environment.
I'd also like to explain the different types of sound deadening, as there is a TON of misinformation out on the web about this stuff
1) Constrained Layer Dampers, aka CLD. These types of products, typically referred to as "dynamat" are the most popular types of sound treatment in the aftermarket automotive world. They are meant to reduce resonance of panels via using their 2-layer composition. The butyl rubber layer uses its viscoelastic properties in reference to the aluminum constraining layer to create sheer resistance, which converts mechanical energy into low-level thermal energy. They do NOT work by adding mass. Adding mass only lowers the resonant frequency of the panel you are adhering it to. CLD does a little bit of that (since it does add weight), but mostly lowers the Q of the resonance peak. These typically SEEM to lower road/tire/exhaust noise, but they actually don't help much for these directly. What they usually fix is just the resonance of panels that is caused by those sounds. How much these will lower the overall noise floor of a given car entirely depends on the car. Also, the range of level of quality in these products is absolutely absurd. Do not cheap out. Do it once, do it right.
2) Decouplers, typically Closed Cell Foams, aka CCF. These products, usually called CCF (Dynaliner being one of these products) are the next most popular sound treatment product in the aftermarket automotive world. The purpose of these products is to decouple two hard panels from resonating against each other and providing a cushion so they don't create annoying buzzes and rattles. They are also used to decouple and provide an air gap for noise barriers (the next type of product) to allow them to be as effective as possible. What they do not do is absorb any meaningful amounts of noise, and they definitely do not block any outside noise. That brings us to the next product..
3) Noise Barriers, typically being mass-loaded vinyl, aka MLV. Noise barriers are used to BLOCK outside noise. If you want to get rid of tire noise, exhaust drone, etc.. this is it. The problem with noise barriers is that you cannot just spot treat with them. It's pretty much all or nothing. A lot of people are now starting to use encapsulated lead style products since they are much thinner, are moldable, and are even more effective and easier to work with than their MLV counterparts.
If you want to learn more about these and how they work, here ya go.
Back when I had my 991.2 GT3 you can throw a thick blanket on the rear shelf and it will lower the engine volume in the interior a considerable amount. This is great if you don't want to do anything costly or permanent. Or just want to keep the car as-is for those weekend 1 hr drives but want to have a quick remedy for the long 3-4 hr drive.
Got some patterns from coco mats, not what was expected but the process continues. The goal is to get the back fully covered and use a single piece of material. Also I think the pattern is for a gts.
Got some patterns from coco mats, not what was expected but the process continues. The goal is to get the back fully covered and use a single piece of material. Also I think the pattern is for a gts.
Were you able to take this further? I’ve been thinking about something similar recently for my Touring as well, something pre formed that can easily be laid on top of existing carpeting (and removed & replaced easily at will) to reduce some cabin resonance and bring the volume down a notch. If we end up working with a manufacturer might be great to get a run of a dozen or two for interested members too.
doobooloo, I am in the middle of a project precisely along the lines you have contemplated. I am using the canonical blocking and absorbing materials placed inside a form-fitted cover that matches the shape and color of the back space of the GT3. The finished parts will resemble cushions that can be easily inserted and removed from the back space of a GT3. My buddy's wife is stitching the removable covers for the acoustical innards. I should have the complete set of "cushions" in a month or so. I will report back with photos of the project and comment on how successful it was.
Last edited by Professor MSP; 01-11-2022 at 11:25 PM.
Reason: Typo
doobooloo, I am in the middle of a project precisely along the lines you have contemplated. I am using the canonical blocking and absorbing materials placed inside a form-fitted cover that matches the shape and color of the back space of the GT3. The finished parts will resemble cushions that can be easily inserted and removed from the back space of a GT3. My buddy's wife is stitching the removable covers for the acoustical innards. I should have the complete set of "cushions in a month or so. I will report back with photos of the project and comment how how successful it was.
Wow - that is really exciting. Can’t wait to see the results, please keep us posted! Also, would you be open to doing a small run for the community once you get it to the point where you’re happy with the outcome?
doobooloo, I am in the middle of a project precisely along the lines you have contemplated. I am using the canonical blocking and absorbing materials placed inside a form-fitted cover that matches the shape and color of the back space of the GT3. The finished parts will resemble cushions that can be easily inserted and removed from the back space of a GT3. My buddy's wife is stitching the removable covers for the acoustical innards. I should have the complete set of "cushions in a month or so. I will report back with photos of the project and comment how how successful it was.
Early on in the project I told my friend that there would be some interest in the project from Rennlist members. I will get back with him and his wife after I provide forum members with an assessment of how successful the project was and the interested parties have had a chance to see the finished product. The material for the form-fitted covers has been ordered and the innards are complete. I am expecting to see the finished project in less than a month.
Early on in the project I told my friend that there would be some interest in the project from Rennlist members. I will get back with him and his wife after I provide forum members with an assessment of how successful the project was and the interested parties have had a chance to see the finished product. The material for the form-fitted covers has been ordered and the innards are complete. I am expecting to see the finished project in less than a month.
Wow this is super exciting news, less than a month to seeing the finished project! Please keep us posted! 👍👍👍
08-20-2021, 04:15 AM
