The Detroit Doom Jump is a jump that has only ever been made by Mike and Chuck while driving Mutt. Anyone else who's tried has regreted going on it, panicked, and slowed down, causing them to fall and presumably die.
The Detroit Doom Jump was first seen when Mike and Chuck tried to jump it for "fun" during "Power Trip." At the last moments before the jump, they were called to action by the other Burners and gave up. They later returned to the ramp in Mutt boosted by an unstable KaneCo power core, and made the jump while simultaneously saving Motorcity from the massive explosion from the power core.
Even in a city where extreme driving is a favorite hobby, the Doom Jump is covered in warnings NOT to try it.