When you eliminate the internal combustion engine from a car, the lack of engine noise highlights other sounds that would have otherwise been drowned out. This is actually a big issue for engineers working on electric vehicles, and one of the biggest sources of peace disturbance in the cabin are the tires.
Tire roar is really noticeable in EVs, in some cheaper vehicles it’s almost a problem, but tire manufacturers are working on ways to improve their products specifically for electric vehicles. Our own Kyle Conner visited one of GoodYear’s tire testing facilities, in the middle of nowhere, close to San Angelo, Texas, to learn more about the process of making EV-specific tires and especially the foam that they now put in tires to help quiet them down.
In this video uploaded to our YouTube channel, you’ll get to see just how big a difference said foam makes. GoodYear showed us what tires without foam sound like and how loud they are, then they switched to the same tire but with foam inside to allow us to observe the difference.
The phenomenon that causes the so-called ‘tire roar’ is cavity resonance, or, in other words, sound waves bouncing around inside the empty tire. The aim of the foam is exactly to dampen the sound and the result is really quite noticeable, as you’ll see in the video. The vehicle the tires were tested on is a Tesla Model S P90D; the exact same car is used for both tests (with and without the foam).