Guide to Heat Shielding and Sound Deadening
Part of the fun in driving a hot rod is the arousal of your senses thanks to the sight, sound and feel of motoring down the road (not so much on smell and taste). With our older cars however, there can easily be sensory overload with the excessive engine or road noise along heat blazing through the firewall or transmission tunnel.
Sure a little noise or heat during a short cruise or in a vintage hot rod can be part of the experience or even charm, but over time, that warmth and noise will weigh on you and anyone that comes along for the ride. As we plan and build our classics to enjoy over the road, taking the time to block out excessive road noise and heat will make your trip much more enjoyable, as well as your passengers.
When it comes to road noise, we’re talking much more than just a loud exhaust. There’s engine noise, wind noise, tires and a plethora of vibrations from sheet metal panels and connections. The most effective way to dampen vibrations and create an effective acoustic barrier is by installing a sound deadening material that can be applied to the sheet metal or fiberglass floor.
There are many different materials ranging from foams, rubber materials or effective butyl compounds in a number of thicknesses available to fit any application. The most popular products come in panels that adhere to the floor and have a thin foil or aluminum backing. 
In most applications, applying this material to 50% – 75% of the floor or panels provides solid protection, though most everyone seems to coat the entire floor, which works just fine too.
While sound deadener will help a little with lowering heat, there are other materials designed to handle heat sources. From insulation panels for the floor or headliner to reflective materials and unique composites backed by specialized aluminum materials, there’s a heat blocking material for every application. Not to mention header wraps or pipe shields, or protective heat sleeves for wiring or fuel lines. Where there is excessive heat, there are helpful solutions to consider.
We took a look at some of the latest offerings to quiet your interior and block the heat so everyone can enjoy the ride.
Speedway Motors
All-in-One Kit
A hot rod should sound like a hot rod, but that doesn’t mean you need to settle for a noisy cabin and deal with heat rising from the floor. Speedway Motors has made it easy to seal the heat out while dampening noise at the same time with their Universal Aluminized Heat/Sound Insulation & Install Kit.
This handy kit will cover up to 24 square-feet with an industrial grade aluminum laminated sheet with 3/8-inch of fiber tech padding. The padding reduces road noise while its aluminum backing enhances heat reflection to reduce cabin temps. To help complete your project, Speedway includes a 2-inch roller, a heat resistant adhesive and a roll of aluminum sealing tape.
Second Skin
Quieting Old Cars
Old cars have never been known to produce a quiet drive as there always seems to be some sort of exhaust or road racket not to mention the structural noise from vibrations in the sheet metal panels. Second Skin battles both with their Damplifier Pro and Luxury Liner Pro in a single Vehicle Build Kit.
Second Skin offers packages for everything from compacts to full size cars and SUVs. Their Damplifier Pro mats are 2mm of American made butyl rubber (no asphalt) with a thick, annealed foil shell. Once applied to the floor, doors or firewall, it gets covered by the Luxury Liner thermal insulation barrier to block out airborne noises from the exhaust, tires and engine. This material fuses a decoupling foam layer to a dense mass loaded vinyl for extreme heat and noise protection. Combined, these two materials will reduce the noise level in your car or truck cabin by 10+ decibels when driving at highway speeds.
TIPS from the PROS #1 – Roadster Shop
With the number of trick builds rolling out of The Roadster Shop, they’ve learned what works best when it comes to reducing and protecting against heat. “We tend to always lean more towards the overkill side of things when it comes to heat and Noise/Vibration/Harshness mitigation,” explained Josh Henning of the Roadster Shop. “No matter how you build the exhaust it still gets extremely hot so we wrap it with DEI’s Titanium header wrap. We also shield the floors, tunnel, gas tank, fluid lines and more. The overall driving experience is so much more pleasant when your feet aren’t cooking and the A/C isn’t struggling to keep up.”
“Remember,” Josh added, “You will never be out on a hot day and wish you HADN’T shielded something…but you sure will wish you had!
Design Engineering Inc.
Tunnel Protection
A lot of heat gets transferred into the interior right through the transmission tunnel as well as the rest of the floor, especially right above the exhaust system. To combat radiant heat from entering the interior, Design Engineering Inc. developed their Floor & Tunnel Shield II thermal material. 
Not only is the material highly effective, it’s also easy to form and shape for installation.
The Shield features an embossed 10-mil aluminum sheet bonded to a punched high temp resistant fiber composite spacer that is lightweight and easy to cut. The material can be installed between the transmission and the tunnel thanks to a super strong adhesive that withstands water and wind. The material will withstand direct temps up to 1,750 degrees F and adheres to nearly any surface ranging from metal to fiberglass. DEI offers the Floor & Tunnel Shield in a number of different sizes to fit any applications.
Heatshield Products
Keep a Cool Head
Everyone points their fingers at the floor of their vehicle as the main source for interior heat and noise but you may want to stop and look up for a moment. You see, the roof is also a large entry way for heat and noise as it soaks up the solar energy of the sun while the thin sheet metal transfers it right into the passenger compartment. 
This is exactly why Heatshield Products developed their db Headliner Kit.
The db Headliner Kit consists of db Skin and their thin Stealth Shield to produce an effective heat and sound insulation between the headliner and the roof. At only 1/8-inch thick, Stealth Shield won’t cause fitment issues with the headliner and the db Skin liquid sound damper effectively dampens the panel against vibration over a range of 10 to 40 KHz. The result of installing the USA made db Headliner Kit is a significantly cooler and quieter interior.
TIPS from the PROS #2 – Charlie’s Custom Creations
When it comes to heat and noise protection, Charile Swanson and his team at Charlie’s Custom Creations, make sure to cover their bases to dampen noise and keep the heat out of the cabin. “We apply Boom Mat from the firewall back, including the doors and even the roof of the car. It makes a huge difference in cabin noise compared to a car without the material.” As for heat, Charlie added that they go back over the firewall area and trans tunnel with a heat blocking material. “In fact, we’ve started applying an aluminum faced Tunnel Shield between the trans and the floor as an added layer of heat protection.”
Lizard Skin
Desert Skinned
The skin of a lizard is designed to withstand harsh environments so it makes perfect sense to protect your vehicle from heat and noise with the help of LizardSkin, and their water-based, environmentally friendly coatings.
Two spray-applied solutions are available to produce a cooler, quieter driving experience. A Ceramic Insulation (CI) formula keeps your car cool by drastically reducing heat transfer into the interior from the driveline and sun, while LizardSkin’s Sound Control (SC) material knocks down panel vibrations, noise from road and other exterior sources. The coatings are applied with shop air and their SuperPro Application Kit, a specialized gun built to handle the viscous coatings. This application method allows for 100% coverage of the substrate and will add an extra layer of protection against moisture.
QuietRide Solutions
Pre-Cut and Ready
QuietRide Solutions has done a serious amount of R&D to save you time and aggravation when fitting and finding the right materials for your application. QRS offers over 1,300 different year-make-model kits featuring pre-cut, ready to install AccoustiShield Insulation Kits for Ford, GM, Chrysler and British vehicles built from 1930 through 2016.
Their two-stage acoustic products cover the entire interior of the vehicle from the toe-boards to the taillights including the rear wheel wells, fenders, package tray and seat divider. Each kit incorporates Dynamat’s Xtreme material to stop body panel vibration and HeatShield’s thermal barrier insulation panels to trap the sound and insulate the interior. The result is a reduction in passenger cabin noise by 50% and cutting radiant and reflective heat by 25 degrees F. They also offer pre-cut Firewall Insulator panels and AcoustiHood systems.
Thermo-Tec Automotive
Header Wraps
Thermo-Tec has been studying heat and sound control technology for over 35 years and one area of expertise is with their Header Wraps. There are many benefits to using a header wrap from lower under-hood temperatures to improved exhaust scavenging resulting in more power. If these benefits sound good to you, check out Thermo-Tec’s Gen II Copper Header Wrap.
As the only copper infused wrap available, this exclusive technology improves heat resistance up to 30% more than other technologies. The Copper Wrap can withstand continuous heat up to 2,000 degrees F! Thermo-Tec offers this material in 50-feet rolls in either 1 or 2 inches wide with a low profile of 1/16 inch thicknesses.
TIPS from the PROS #3 – Goolsby Customs
Protection against heat plays a big role in project vehicles that roll out of Goolsby Customs. “We’ve been using the Floor & Tunnel shields between the trans and the floor of the car to block the heat of the transmission on all of our builds,” Jonathan Goolsby said. “Adding extra heat protection and sound dampener is a given with any build any more. People are driving their cars more and making sure they stay cool and keeping it quiet improves the driving experience.
Jonathan explained that there are a lot of helpful products to add extra protection throughout any car. “If the exhaust is close to the gas tank we apply a gold reflective tape, or protect other wires and lines with a sleeving. Every little bit helps to add protection for a trouble-free drive.”
Summit Racing Equipment
Sticky Sound Barrier
No matter what you’re working on, you can be sure that Summit Racing Equipment has a package of their Ultimate Heat Barrier and Sound-Deadening Mats to fit your application – and budget.
Their Mats will keep you and your passengers more comfortable when cruising by blocking excess heat and noise from the interior. The self-adhesive mats can handle ambient temperatures up to 400 degrees F are great for use on firewalls, floorboards, wheel wells and doors.
Dynamat
Decked Out
DynaMat has been on the forefront of battling heat and blocking automotive noise for years and now offers a heavy-duty vinyl flooring that not only looks great, but serves as an effective barricade against heat and noise. 
Their DynaDeck is an ultra-durable vinyl and thermo-acoustic foam carpet and padding replacement that will stop noise and heat.
The durable, deep twist, embossed DynaDeck mat has the perfect vintage texture and look to fit hot rods, classic sports cars, trucks, and classic off-road vehicles. With excellent wear characteristics, this floor mat composite is designed for application in any area that requires a high noise transmission loss, good heat insulation and abrasion resistance. The material is completely weather proof, oil resistant and wear resistant. It is available in brown, green and black finishes in lengths of from 3 – 25 feet.
TIPS from the PROS #4 – Murray Kustom Rods
When it comes to new builds at Murray Kustom Rods, they already know they’re going to use a sound dampening material as well as added heat protection. “Both get installed on all of our builds,” Heath Murray explained. “It changes the entire dynamics of the car. By applying the sound and vibration material in the doors, they feel and sound so much more solid. It’s just what people expect today.”
“For heat, such as in the roof, we apply a different material that is lighter weight and more of a stick-on foam. In Texas, blocking out as much heat as possible is important and much more comfortable on long drives.”
Edelbrock
Cool Fuel
Today’s modern fuel blends can wreak havoc on carburetors, especially when things get seriously hot under the hood. Fuel can actually boil away in the fuel lines or float bowls causing driveability issues and tough starting. 
Edelbrock offers a couple different ways to block and stifle engine heat from transferring to the carb with their line of heat insulator gaskets and spacers.
Edelbrock’s heat insulator gasket is designed to help prevent fuel percolation in both open and ported styles. They also offer a number of different height spacers made of a wood fiber laminate or phenolic plastic material to reduce heat transfer and keep you fuel in a liquid state (and maybe even boost some low-end torque with a tall spacer).
Hushmat
Tighter Tunes
Blocking out road noise and engine noise will make for a pleasant drive, but what about improving the sound of your favorite driving tunes? Hushmat offers a door kit that features their Silver Foil butyl panels to install and around the door speakers to.
The HushMat Door/Speaker kit creates an anti-vibration gasket between the speaker and the metal door effectively creating a vibration-free speaker enclosure to improve the sound. When the speaker cone moves the vibration of the speaker doesn’t transfer to the metal door to create a distorting vibration. Not only does the Hushmat improve the speaker’s sound quality, but it also dampens the road noise echoing through the door.
