An undeniable hallmark of Suzuki’s GSX-R platform is the inline-four soundtrack. Wearing its ‘screamer’ badge with pride, the litre-sized Gixxer stands at the top of the hill and wails like no other. When Davor and Luka Fabijancic plopped a GSX-R1000 engine into a Citroën C2, it sure sounded the part.

The duo built the Citroën C2 Suzuki Proto for the Croatian Formula Driver Championship but the nimble little machine also participated in other slalom and hill climb events in the country. With a stock C2 featuring a 1.1-litre petrol engine producing 60 bhp and its 1.4-litre diesel counterpart eking out 67 ponies, the Gixxer’s powerplant was a massive upgrade. With its 200 bhp and an 11,000 redline, the Suzuki's inline-four is also much more high-strung than Citroën’s stock motor.

To get the full benefits of the GSX-R1000 mill, the team mounted it right behind the driver. Combine that with the car’s short wheelbase and rear-wheel drivetrain, and it’s no wonder the Citroën C2 Suzuki Proto placed in the top 10 Fastest Touring Cars of the Croatian Formula Driver Championship. As our buddy Bradley Brownell noted over on Jalopnik, motorcycle engines are more “compact, lightweight, quicker to rev, produce more power, and are usually more efficient than a comparable car engine.”

Of course, with the C2 weighing 620 kg (1,370 pounds), the GSX-R1000 engine has to power 430 kg (950 pounds) more, but one thing remains—that unmistakable sound. If you close your eyes and just listen to the YouTube video, you could swear it was a Suzuki superbike banging through the gears. Whether it's on corner approach or driving onto a straight, the GSX-R soundtrack blares from the Citroën. Even on four wheels, the litre-sized Gixxer doesn’t lose that glorious wail.