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Here’s Why Acura’s IMSA GTP Race Car Sounds Just Like Chewbacca

Gives a whole new meaning to "there's a beast under the hood."
Getty Images, Caleb Jacobs

Like most of you reading this blog, I’m a big fan of race car sounds. Naturally aspirated, turbocharged, hybrid, modified or purpose-built, the Symphony of Horsepower comes in many shapes and volumes. That being said, I don’t think I’ve ever heard a race car and immediately thought; “Yup, that’s Chewbacca from Star Wars.” Until now.

Acura’s IMSA GTP hybrid prototype, the ARX-06, is powered by a 2.4-liter, twin-turbocharged, direct-injected V6 gasoline engine paired with an IMSA-specified Bosch electric motor and Williams Advanced Engineering battery pack. All of this amounts to roughly 700 horsepower and a series of funky noises that sound unmistakably like that hairy creature from the popular sci-fi movie.

Motorsport journalist Marshall Pruett and the IMSA folks put together a fantastic YouTube video bringing to light these unique sounds ahead of this weekend’s Rolex 24 at Daytona. And in order to explain how they happen, Pruett interviewed the mastermind behind all the complex engineering: HRC US president David Salters.

As the big boss of Honda Racing Corporation US—up until recently known as Honda Performance Development (HPD)—Salters knows a thing or two about engines. Previously, he was the head of Formula 1 engine development for Mercedes from 2003-2006 and also ran the Ferrari F1 engine and KERS program from 2006-2015. In a nutshell, he gets it.

I won’t transcribe everything Salters says in the video mostly because it’s a lot, but also because he and Pruett do a phenomenal job of breaking down something super complex into easy-to-understand words. Salters teaches an ICE+Hybrid 101 class and even uses his daughter’s horse-jumping experience to describe what the ARX-06 and its driver go through when they enter a corner, drive through it, and ultimately exit it.

I suggest you watch all six minutes of the video—which includes many Chewy sounds—but in a nutshell, it comes down to the physical reactions caused by the interaction between the combustion engine, the electric motor generator, and the traction control system.

Happy watching.

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