Sidewinder (サイドワインダー Saidowaindā) is a highly skilled team that organized the "4 lines of defense", who make their debut in Fifth Stage. Their home course is the Tsubaki Line. They are considered the "fourth line" or the last team in Kanagawa that Project D competes with. In the storyline, this team attempts to analyze Project D's weaknesses throughout Fifth Stage before their initial battles with them. Eiji Kubo acts as the team's chief mechanic and strategist, and does not actively participate in battles. They collect information by watching Project D during their practices and races, which is done by timing them through data collection teams and having Kubo and Go Hojo spectate together during the races leading up to their battle against Project D.
Shinji was recruited to the team after Go recognized his talent and driving skills. Though he was initially reluctant to participate with the team for their battle with Project D, he later on changes his mind and battles Takumi Fujiwara on the downhill.
|Go Hojo||Honda NSX (NA1)||Uphill|
|Shinji Inui||Toyota Sprinter Trueno GT-APEX 2door (AE86)||Downhill|
|Eiji Kubo||N.A.||Chief mechanic/Team strategist|
- Rin Hojo is not a member of Sidewinder, though has appeared alongside them in official art. This is most likely because he raced Ryosuke Takahashi and so is one of Project D's final opponents.