Dr. Tsuchiya heads the Tsuchiya Racing Factory (TRF) and pioneers Mini 4WD development. A former jet pilot and engineer, his expertise directly shapes the aerodynamic and engineering breakthroughs in his lab and car designs, forming the foundation for the prototype Saber series, including the Sonic Saber and Magnum Saber. He provides these cars to Retsu and Go Seiba conditioned upon their victory in national Mini 4WD competitions.

He clashes ideologically with Dr. Ōgami, who promotes destructive "battle racing" tactics. Dr. Tsuchiya champions traditional Mini 4WD racing values: sportsmanship, technical skill, and non-weaponized innovation. This conflict drives the series' tension as he mentors the Seiba brothers and their allies to counter Ōgami. The TRF Victorys team, representing Japan in the World Grand Prix (WGP), operates under his guidance and bears his facility's initials.

He mentors racers like Retsu, Go, and J—a former Ōgami battle racer who defects to his lab, rejecting destructive methods. His laboratory acts as a hub for refining racing techniques and developing new technologies, such as assisting J with advanced Proto Saber iterations.

Two decades later in *Return Racers*, he influences the protagonists' futures. He recommends Retsu for overseas studies, leading to Retsu's space development career, and indirectly supports Go's transition to professional Formula racing. Go later mentors racers like Tsubasa. Dr. Tsuchiya's legacy endures through technological progress and his philosophy of ethical, innovation-driven competition in the Mini 4WD community.