Is there such thing as a T51 torx bit?

Yes, there is a T51 Torx bit. Torx bits come in various sizes, designated by a "T" followed by a number, and T51 is one of the larger sizes used for specific applications, particularly in automotive and industrial settings. It is designed to fit screws with a star-shaped drive, allowing for better torque and reducing the likelihood of stripping the screw head.