DEI Heatshield Install, thermal barrier, installing heat shield

Blocking Heat – DEI Thermal Barriers are Effective and Easy to Install

How long have you put up with toasty-warm feet and legs due to heat radiating through the floor or transmission tunnel? We set out to see how much heat we could block with a little help from DEI – Design Engineering Inc.

One of the most popular products used in new ground-up vintage vehicle builds these days are noise damping panels combined with materials to reduce heat transfer. In fact, several of the builders we spoke to while researching the latest heat and noise blocking products said that taking steps to lower noise and heat wasn’t even an option, but rather a must-have on every project.

After learning a little more about the number of noise and heat blocking products available, we thought it would be interesting to check out a couple different thermal blocking materials. We knew of a ’40 Ford sedan project with no carpet and noticed that the floor was scorching hot to the touch due to the exhaust system being routed through the chassis with the pipes close to the bare steel floor.

Design Engineering Inc. offers a catalog of thermal barriers and noise damping products and their newer Floor & Tunnel Shield II was recommended by several builders. This material is only 3/16-inch thick with an effective insulating material covered by a textured aluminum face to deflect heat. For inside the car they offer several lightweight insulation materials that install under the carpet (aptly named Under Carpet Lite). Two completely different products with different uses but the same goal – reducing heat.

Note that the ’40 is not quite road worthy, but with no carpet and a dual exhaust, it presented a perfect opportunity to set up an A/B test. Our test was to leave the driver’s side as-is for a constant while installing the DEI materials in two steps on the passenger side. The floor temperature was reported with a cheap infrared temp gun. Again, not quite a scientific study, but enough to provide some before-and-after results.

The mild small-block V8 was run for over 15 minutes at about 1,000rpm, and then we noted the temperature of the floor, which was extremely hot to the touch and ended up getting to well over 180 degrees! The two DEI materials knocked the floor temperature down by over 60 degrees! If we were to cover more of the external floor surface and insulate the cabin floor completely, there would be an even bigger drop in temperature.

This little experiment really opened our eyes to how easy it is to make our interiors a lot more comfortable no matter what you drive. Be sure to check out our guide to heat shielding and sound deadening to learn more about what products are available to help cool and quiet your hot rod.

Test Notes

It is important to note that this story is aimed at showing how easy and effective it is to block significant heat from entering the passenger compartment. Measurements were taken with a no-name infrared thermometer on a 95-degree day. (In short, there are better devices, such as a thermal probe, for more accurate readings.) Following the manufacturer’s recommendations and installation procedures will likely produce even better results.

Todd Ryden is first and foremost a car guy and admits to how lucky he is to have been able to build a career out of a hobby that he enjoys so much. He’s owned muscle cars and classics, raced a bit and has cruised across the country. With over 25 years in the industry from the manufacturing and marketing side to writing books and articles, he just gets it.