TV-Series
Description
Jun Kitami, often referred to by the ominous nickname the Tuner from Hell, is a pivotal figure in the story as the original creator of the legendary and cursed Devil Z. He is a middle-aged man with a noticeable large scar on his face, a physical mark that is implied to be the result of a serious accident during his own racing career. Despite his reputation and the fearsome power of the cars he builds, his current life is far more modest, as he works as a mechanic and runs a small bicycle shop.

Kitami possesses a personality as intense and uncompromising as the machines he builds. He is characterized by a near-maniacal laugh in the face of danger and a complete disregard for conventional safety limits, willingly pushing engines far beyond their 600 horsepower threshold. This reckless pursuit of power is the source of his hellish reputation, as the cars he tunes become so potent that they are notoriously difficult to control, leading to numerous accidents and even deaths for those who attempt to drive them. His obsession with performance has come at an immense personal cost; his devotion to perfecting the Devil Z led to his factory going out of business and the loss of his family. Yet, when questioned about his life choices, he has declared himself the happiest man in the world, demonstrating that his passion for cars has become his sole, all-consuming purpose.

Kitami is a traditionalist with strict technical requirements. He holds a strong preference for carburetor engines over modern fuel injection systems, a reflection of his old-fashioned and purist approach to tuning. This stubbornness is evident even when he agrees to tune Tatsuya Shima's Porsche 964, known as the Blackbird. He only took the job to create a car powerful enough to challenge his own creation, the Devil Z, and complained extensively throughout the process due to his dislike for the car's fuel-injected engine.

In his younger days, Kitami was a professional GT racer and a driver-mechanic. His past on the circuits and the Tomei Expressway is a tragic catalogue of ambition and disaster. After a history of accidents involving cars he tuned, clients stopped seeking his services, leading to bankruptcy and debt. It was from the remaining parts in his bankrupt workshop that he built the final S30Z, the car that would become the infamous Devil Z. This history gives him a unique insight into the vehicle, and he comes to believe that only the protagonist, Akio Asakura, has the innate ability to tame the Devil Z and save it from destroying itself and its driver.

His key relationships are therefore central to the plot. He serves as a mentor and ally to Akio, helping him understand and control the Devil Z. Simultaneously, he engages in a competitive partnership with Tatsuya Shima, tuning the Blackbird to be the Z's ultimate rival. Kitami does not engage in street racing himself anymore; his role is that of the brilliant, haunted engineer working from the sidelines. His most notable ability is his genius-level tuning skill, which is both revered and feared. His work creates cars with overwhelming, undriveable power, and he is the sole person capable of maintaining and modifying the Devil Z. He also owns and drives a Nissan Fairlady Z (S30) of his own.