Less Noisy Nova: Project Swinger Gets Dynamat Xtreme Custom Cut Kit

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Of all the things that make classic musclecars awesome, their ability to keep the cabin nice and quiet and free from exhaust heat is just not one of them. Those of you who own a musclecar, or who have at least ridden in one, know exactly what we’re talking about. Sound deadening and insulation on these cars was at best marginal even when they were new, and when you mix in 40-plus years of deterioration to those OEM materials things can get downright noisy and hot.

 

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Now that Swinger’s exterior is pretty much finished we can turn our attention to the interior and get started with Dynamat.

That was exactly the situation we found ourselves facing with our 1971 Nova, Project Swinger. Swinger is shaping up to be a top-shelf pro-touring ride built from some of the best performance parts on the market. It’s powered by a 556 horsepower Chevrolet Performance Parts supercharged LSA crate engine which is backed by a Tremec TKO 5-speed and a Currie 9-inch rearend. Swinger is suspended by a full Air-Ride system from Ride Tech, and rolls on a wicked set of 18-inch Forgeline SP3P wheels bolted over big SSBC brakes. We’ve outfitted the Nova with mini-tubs, new floors, new glass, new bright-work, and even a fully digital dash from Dakota Digital.

We're constructing Swinger with some of the most refined parts the aftermarket offers, including a supercharged LSA crate engine and a Dakota Digital dash. So, we want the interior to be on par - quiet and refined.

In addition to all that performance and style we wanted to add some refinement and comfort to Project Swinger, and one of the best ways to do that is to add better sound deadening and insulation. Luckily our buddies at Dynamat had exactly what we needed to tame the noise and heat level of Swinger’s interior, and do it in the most simple and easy manner possible with their Custom Cut Xtreme kits. Follow along with us as we lay out the technical aspects of Dynamat’s sound control products, and detail our own installation in Project Swinger.

Dynamat Custom Cut Kits

Dynamat Xtreme Custom Cut kits

You’re likely already familiar with Dynamat because they have long been known as the leader in products to kill unwanted vibration, noise, and heat in cars and trucks. They have everything from bulk sheets for custom installs to sound deadening carpet and lightweight materials for race cars. The particular product we went with for Project Swinger is the Dynamat Xtreme Custom Cut kits for 1968 to 1972 Novas.

The beauty of the Custom Cut kits is that Dynamat does most of the work for you. The sheets are already die-cut into the exact shape of the body panels of many popular applications, and are adhesive backed for easy installation. We used the Dynamat Custom Cut Xtreme kits for the 2nd Gen Nova on the doors (Part # XGM N2 D), floor (Part # XGM N2 F), rear seat (Part # Part # XGM N2 U), package tray (Part # Part # XGM N2 P) and trunk (Part # Part # XGM N2 T).

We spoke with Beth Maranda, Managing Director at Dynamat and wanted to know how far back some of their Custom Cut kits cover, and how they go about deciding which cars to make these kits for. She said, “First we have to decide on what vehicles are popular, which are getting restored more often than others. The second thing we have to consider is if we can actually get the car, and if it’s stock.”

Since their kits can go as far back as a 1932 Ford, or the Tri-5 Chevrolets, you can imagine that finding a car that hasn’t been modified or customized is a bit of a challenge. But they have been doing these kits for a little over four years now, and their coverage has been quite extensive, and keeps growing.

Dynamat Xtreme Tech Specs

Ease of install isn’t the only thing the Xtreme Custom Cut kits have going for them. Dynamat Xtreme is constructed of a high-tech “elastometric butyl” covered in a thin aluminum layer that is made to conform to the shape of whatever surface it’s installed on. Essentially, it is original Dynamat on steroids.

Dynamat Xtreme works by absorbing the noise and vibrations that a car, especially an older one, naturally makes as it is being driven. It might sound simple, but the real magic comes from the materials. The energy from the noise and vibrations is then transferred into silent energy by the elastometric butyl, while the aluminum outer layer protects the cabin from excess heat radiating from the outside.

Dynamat Xtreme is a 0.067″ thick layer of elastometric butyl covered in a flexible layer of aluminum that absorbs sound and vibration while deflecting heat.

So, just how well does this stuff work? Well, Dynamat’s tests have shown that employing a thorough regimen of Dynamat Xtreme similar to what we are using in Swinger can lower interior sound levels by as much as 18 decibels. That’s like taking the sound level inside your car as it goes down the highway from the same level as a manufacturing facility (80 db) down to the level of a normal phone conversation (60 db).

These test results show the level of harmonic distortion measured in a regular car door without Dynamat, with Dynamat Original, and finally with Dynamat Xtreme. As you can see the amount of excess vibration and resonance is drastically reduced once Dynamat is installed.

Although we are using it primarily as a sound deadener and heat barrier, the Dynamat Xtreme will also pay huge dividends when we crank up the tunes on a long cruise. That’s because lowering the overall sound level inside the interior means that the nuanced sounds of our music will now make it to our ears without adding more amps or turning up the volume. Vibrations and resonance coming from the interior body panels will be replaced by clearer treble and cleaner bass.   

Peel, Stick and Roll: Installing Xtreme Custom Cut in Project Swinger

Installing Dynamat was always part of the master plan for Project Swinger, and as such we haven’t yet put the interior back in the car. As it sits after being painted it’s a perfect blank slate to add the Dynamat to. Of course if your car does have the interior installed removing everything would naturally be the first step in the process since Dynamat installs under your carpet and behind all the interior panels.

We were lucky in that we didn't have to remove anything to instal the Dynamat, just prep the surfaces.

Our first step was to come up with a plan of attack. We opened up all the packaging and carefully laid out the pre-cut Custom Cut Xtreme sheets in a logical order as to how they would go in the car. If you’re doing an entire car like we are, this is a very important step since you don’t want to paint yourself into a corner with Dynamat and have to step all over it to get in and out of the car.

The pre-cut Custom Cut kits for different parts of our Nova were incredibly convenient, and made our install quick and easy.

The importance of a clean and dry surface to mount the Custom Cut Dynamat on cannot be overstated, so to help promote adhesion we gave the entire interior a thorough dusting and degreased spots that looked like they could use it. Keeping the surfaces nice and clean will be an on-going task through-out the install since you’ll be climbing in and out of the car quite a bit, so be sure that every surface is clean and dry before you stick the Dynamat.

We kicked off the Dynamat install with the doors - an area we wouldn't mess up climbing in and out of the car.

We started with the doors, and after a quick test fit, we peeled the paper backing off and lined up the Dynamat exactly where it needed to go. Be sure to take your time lining things up, because once the Dynamat sticks to a surface it’s not going to come off without a fight. We stuck on the top of the door first and worked our way down to the bottom peeling and sticking every few inches.

We started at the top and slowly worked our way down the panel, and finished off with the Dynaroller to get all the air pockets out.

Letting The Air Out

The next step is to go over the entire area and press the sheet into any voids and smooth out any trapped air pockets. The sheets need to be perfectly flat against the mounting surface because air pockets can greatly reduce the Dynamat’s effectiveness. Luckily Dynamat makes two specific products to handle this important task – the Hardwood Dynaroller (Part # 10005) for the at-home installer, and the Heavy Duty Dynaroller (Part # 10007) for more complex or professional installations. We highly recommend picking up one of these tools at the same time you purchase your Dynamat. We used the Heavy Duty Dynaroller and it was a breeze getting all the air pockets removed.

Next we laid the Dynamat on the rear quarter windows, package tray, and floor pan.

We trimmed around any areas that needed it using a sharp razor knife or scissors, and moved on to the rear package tray and the area behind the rear quarter windows. This was the most difficult part of the install mostly because of the limited work space available to get the Custom Cut sheet lined up properly. We continued with the area under the back seat, and the rest of the floor pan all the way up to the firewall, which were both very easy to lay down and smooth out. We finished up the install with the trunk, and recycled any Dynamat scraps we had left over by using them as insulation around the Air-Ride compressor.  

We finished up with the trunk and cut the Dynamat to fit around our fuel cell. We also used the left over scraps to insulate around our Air Ride compressor.

The Final Gear

Even as much variance as there can be on the bodies of classic musclecars, Dynamat still did a superb job creating the Custom Cut kits for our Nova. We found that there was really only minimal trimming and tweaking required to get everything to fit exactly how we needed it. Best of all, we had the entire job completed in just a few hours thanks to the pre-cut peel and stick sheets and the specialized Heavy Duty Dynaroller.

A custom kit can usually be installed in a couple of hours, but it can take up to ten hours to install them by the sheet. -Beth Maranda

Maranda said, “Many of our installers like the kits much better than trying to install regular square sheets. A custom kit can usually be installed in a couple of hours, but it can take up to ten hours to install them by the sheet. The pre-cut kits will give you about 80 to 85% coverage.” Of course, she mentioned that there are some who want complete coverage and will buy boxes of square sheets and spend the extra time to cut all of the sheets and install them one by one, but she feels the time saved on the pre-cut kits makes them worth it.

Project Swinger is nearing completion and now we know that when we do finally hit the road we’ll have a refined and quiet interior cabin that will only let us hear the sounds we want to hear – loud music, the roar of the engine, and the squeal of the tires. We’re getting closer to completing the Nova every day, so stay tuned for more updates on Project Swinger!

If you’re looking to make things a little more quiet in your musclecar or street rod, check out the Dynamat web site and see if they have a custom cut kit for you. They also have all the tools you’ll need to install your peace of mind.

Swinger is sound-proofed and finally ready for carpet, door panels, and seats.

About the author

Clifton Klaverweiden

Clifton has been a car fanatic since his late teens, when he started the restoration of his '67 Camaro. He considers himself a student of automotive science and technology, and particularly loves all things LSX. And, although he has an appreciation for everything, from imports to exotics, his true passion will always be for GM musclecars.
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