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InTheGarageMedia.com
The Sound of Silence and Keeping Your Cool
OEM-Quality Insulation for Your Classic Performance Car
BY Ron Ceridono Photography by Jason Scudellari
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here was a time many years ago, around the time Editor Licata got his first Ramones T-shirt, that for many of us the comfort level inside a performance car wasn’t a concern. We put up with noise levels that were similar to being inside in a 55-gallon drum during a hailstorm and temperatures that rivaled those found in Death Valley during the summer—youthful enthusiasm often overrides pain and discomfort. But things have changed; today most of us expect more from our cars than we used to, which includes a quiet, comfortable interior.

When auto manufacturers began taking passenger comfort more seriously in the late ’80s (primarily due to advertising campaigns on the subject by Lexus), they began to search for products to meet the challenge of sound reduction and reduced heat absorption. A company named Dexter Automotive had a specially compounded butyl rubber that proved to be that product and it was approved by General Motors, Chrysler, and other manufacturers for use in production vehicles. Today that company is HushMat and the product is known as HushMat Ultra, which is the only OEM specified and approved sound deadening and thermal insulating material available to the automotive aftermarket.

To emphasize the need for such products to performance car enthusiasts, Tim McCarthy, owner of HushMat, likes to ask this simple question: “Do you ever drive on the highway at 65-70 mph and then exit? When you come to a stoplight, what is the first thing you do? The first thing you do is turn the radio down because it is too loud! The noise in your vehicle while driving on the highway forced you to turn up the volume so you could hear it over the noise.” That pretty well sums up the situation many of us have gotten used to, but it doesn’t have to be so. According to McCarthy, installing the full complement of HushMat products can reduce interior sound levels from outside sources by over 50 percent with the added benefit of reducing interior surface temperatures by over 70 percent.

When shopping for HushMat Ultra you’ll find there are two different versions of the product, HushMat Ultra Silver and HushMat Ultra Black—the only difference is the color of the foil top layer and that Ultra Silver can be painted but it’s not recommended for the Ultra Black (not all paints will stick to the black coating). In terms of performance, these products are identical; they easily mold and form as needed and adhesion is guaranteed for the life of the vehicle.

Along with HushMat Ultra, the company offers several other products that provide sound deadening and thermal insulation:

Silencer Megabond Sound Absorbing and Thermal Insulating Foam: It is used in place of the old-style Jute material commonly used under carpeting. It has outstanding thermal-insulating, sound-absorbing qualities. It doesn’t absorb moisture like Jute and adds an additional 30 percent thermal insulation over and above HushMat Ultra.

Wave Breaker: This material creates a defecting barrier between the speaker and the metal door. When the speaker cone moves the soundwaves will not reflect off the metal door and take the speaker out of phase, which diminishes audio quality.

Hood Liner: Placed on the underside of the hood, it keeps the paint safe from damaging heat from the engine and exhaust system.

Quiet Tape: Used to protect and secure wiring harnesses and cables, this single-sided foam tape is 1-inch-wide self-adhesive foam tape. It can be removed and used over again with no loss of adhesion.

It’s important to note HushMat manufactures their products in the USA to ensure they are made to exacting standards from the highest quality and best materials available. Unfortunately, it’s a sign of the times that there are a variety of counterfeit, offshore products of all sorts being sold by unscrupulous vendors online. So, to make sure you are getting genuine HushMat products, always buy from one of the suggested retailers on their website.

Adding HushMat products to your car is a quick, easy, and affordable way to reduce heat entering the passenger compartment and reduce road and running gear noise. It’s a great way to have a performance car that’s comfortable too, but if you still miss the old days, just dig out a vintage T-shirt.

HushMat insulation is comprised of layers of special butyl rubber with a thin aluminum foil barrier on top. The foil reflects heat and vibration back into the rubber for effective control of both.
1. HushMat insulation is comprised of layers of special butyl rubber with a thin aluminum foil barrier on top. The foil reflects heat and vibration back into the rubber for effective control of both.
HushMat offers custom vehicle kits, like the one we used for this Chevelle, or it is available in bulk in a variety of sizes. Performance enthusiasts needn’t worry about excessive added weight, as HushMat Ultra weighs 0.47 pound per square foot.
2. HushMat offers custom vehicle kits, like the one we used for this Chevelle, or it is available in bulk in a variety of sizes. Performance enthusiasts needn’t worry about excessive added weight, as HushMat Ultra weighs 0.47 pound per square foot.
HushMat Ultra is self-adhesive. Just remove the paper backing and press it in place for a permanent installation.
3. HushMat Ultra is self-adhesive. Just remove the paper backing and press it in place for a permanent installation.
Installing HushMat requires very little surface prep. Simply remove any loose debris, then wipe the surface off with a damp rag.
4. Installing HushMat requires very little surface prep. Simply remove any loose debris, then wipe the surface off with a damp rag.
A trial fit of each section will indicate if any trimming is necessary. Here, Jason Scudellari measures and marks a section to be cut.
5. A trial fit of each section will indicate if any trimming is necessary. Here, Jason Scudellari measures and marks a section to be cut.
To ensure this section of the insulation kit was centered on the driveshaft tunnel, Scudellari made alignment marks on each. It was then trimmed and positioned with the marks as a guide.
6. To ensure this section of the insulation kit was centered on the driveshaft tunnel, Scudellari made alignment marks on each. It was then trimmed and positioned with the marks as a guide.
When required, trimming HushMat Ultra is easily done with scissors or a utility knife and a straightedge.
7. When required, trimming HushMat Ultra is easily done with scissors or a utility knife and a straightedge.
Installation of HushMat Ultra is accomplished by simultaneously pressing it in place while removing the paper backing. If you’re not happy with the placement, there’s approximately a 2-minute window during which it can be removed and repositioned.
8. Installation of HushMat Ultra is accomplished by simultaneously pressing it in place while removing the paper backing. If you’re not happy with the placement, there’s approximately a 2-minute window during which it can be removed and repositioned.
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9. HushMat Ultra is thin (1/16 inch) and is easily formed to follow the contours and irregularities in the floor.
Although HushMat Ultra can be installed by hand, a roller (available from HushMat) will speed up the process.
10. Although HushMat Ultra can be installed by hand, a roller (available from HushMat) will speed up the process.
As HushMat Ultra is thin, overlapping sections won’t show up as lumps and bumps in the carpet.
11. As HushMat Ultra is thin, overlapping sections won’t show up as lumps and bumps in the carpet.
An added benefit of HushMat Ultra is that it prevents water and air intrusion that can cause sheetmetal to rust.
12. An added benefit of HushMat Ultra is that it prevents water and air intrusion that can cause sheetmetal to rust.
Here the rear floor section has been trimmed to fit around the wheelhouse. Note how a hole has been cut to accommodate the rear seat bracket.
13. Here the rear floor section has been trimmed to fit around the wheelhouse. Note how a hole has been cut to accommodate the rear seat bracket.
As HushMat Ultra is easily formed a small piece was shaped to follow the contour of the wheelhouse and blends into the floor section.
14. As HushMat Ultra is easily formed a small piece was shaped to follow the contour of the wheelhouse and blends into the floor section.
In most cases any trimming HushMat products for any protrusions is best done during a test-fit and removal of the paper backing.
15. In most cases any trimming HushMat products for any protrusions is best done during a test-fit and removal of the paper backing.
Installing a large section HushMat Ultra in the doors is easily done by dropping it through the window opening with the glass removed. If the glass is in place, the next best thing is to apply small sections through openings in the inner door panel.
16. Installing a large section HushMat Ultra in the doors is easily done by dropping it through the window opening with the glass removed. If the glass is in place, the next best thing is to apply small sections through openings in the inner door panel.
With the insulation slipped into the door, Scudellari used a roller to press it in place. Insulating the doors and quarter-panels reduces a significant amount of vibration and road noise.
17. With the insulation slipped into the door, Scudellari used a roller to press it in place. Insulating the doors and quarter-panels reduces a significant amount of vibration and road noise.
The sections of quarter-panel insulation were also installed through the window openings as the glass had been removed.
18. The sections of quarter-panel insulation were also installed through the window openings as the glass had been removed.
Although the inner surface of the quarter-panels are not covered completely, there will still be a noticeable reduction in road noise.
19. Although the inner surface of the quarter-panels are not covered completely, there will still be a noticeable reduction in road noise.
The trunk of most cars can be a major source of road noise; insulating the inner quarter-panels helps to reduce it.
20. The trunk of most cars can be a major source of road noise; insulating the inner quarter-panels helps to reduce it.
 Insulating the floor of the truck helps eliminate heat and sound generated by the exhaust system and running gear.
21. Insulating the floor of the truck helps eliminate heat and sound generated by the exhaust system and running gear.
The roof can be a huge source of heat gain in the passenger compartment; HushMat Ultra will reduce that dramatically. One of the obvious advantages of keeping heat out of the passenger compartment is that it lessens the load on the air conditioner, making it more effective.
22. The roof can be a huge source of heat gain in the passenger compartment; HushMat Ultra will reduce that dramatically. One of the obvious advantages of keeping heat out of the passenger compartment is that it lessens the load on the air conditioner, making it more effective.
HushMat’s Silencer Megabond is a sound absorbing and thermal insulating material. It absorbs high-frequency airborne sound, such as engine, road, and wind noise up to 6,000 Hz. It can be applied on top of HushMat and adhesion is guaranteed.
23. HushMat’s Silencer Megabond is a sound absorbing and thermal insulating material. It absorbs high-frequency airborne sound, such as engine, road, and wind noise up to 6,000 Hz. It can be applied on top of HushMat and adhesion is guaranteed.
Silencer Megabond is available in three thicknesses: ½-inch is applied as under-carpet pad; ¼-inch is used on the back of headliners and door trim panels; ½-inch is an anti-rattle gasket material for the back of plastic trim panels, console trays, and gloveboxes.
24. Silencer Megabond is available in three thicknesses: ½-inch is applied as under-carpet pad; ¼-inch is used on the back of headliners and door trim panels; ⅛-inch is an anti-rattle gasket material for the back of plastic trim panels, console trays, and gloveboxes. 
Wave Breaker is made of variable cellular rubber; it is installed on surfaces behind speakers. The foam reduces distortion by breaking up back waves from the rear of the speaker. The result is a cleaner, crisper sound.
25. Wave Breaker is made of variable cellular rubber; it is installed on surfaces behind speakers. The foam reduces distortion by breaking up back waves from the rear of the speaker. The result is a cleaner, crisper sound.
Quiet tape is used to cover and protect the wires of electronic components. It can also be used between surfaces to prevent rattles and unnecessary wear and tear.
26. Quiet tape is used to cover and protect the wires of electronic components. It can also be used between surfaces to prevent rattles and unnecessary wear and tear.
Tech Center
HushMat
(913) 599-2607
hushmat.com