• A purported document suggests Ford could be planning a Mustang Shelby GT500 for 2026.
  • It claims the model will use a Legend engine, which could go into production late this year.
  • If the document is authentic, the new engine is presumably based on the supercharged 5.2-liter V8.

Shelby American recently struck out on their own with the Shelby GT350, but a new document suggests Ford could be cooking up a Mustang Shelby GT500. Furthermore, it could arrive as early as next year and fill the giant gap between the Mustang Dark Horse and Mustang GTD.

While any purported document should be taken with a grain of salt, one recently surfaced on Reddit and was allegedly from UAW Local 600, which is based out of Dearborn, Michigan. Its members work at the Dearborn Engine Plant, Dearborn Stamping, and the Dearborn Truck Plant.

More: 2020 Ford Shelby GT500 Is The Fastest, Most Powerful Mustang Ever

Background aside, the document says “I anticipate an afternoon shift being added towards the end of 2025 on the Niche assembly line. This volume increase is for the 2026 Mustang Shelby GT500.” The unnamed writer goes onto say, “I can’t wait until we start building engines for such an iconic vehicle with an engine that will be named Legend.”

2026 Shelby GT500 leak
byu/TheMaddSage inMustang

Road & Track notes the Niche engine line currently builds the supercharged 5.2-liter V8 that powers the F-150 Raptor. This could suggest the rumored Legend engine is a variation of that same V8.

While we probably shouldn’t read too much into things at this point, the Mustang GTD has a supercharged 5.2-liter V8 producing 815 hp (608 kW / 826 PS) and 664 lb-ft (900 Nm) of torque. The old Shelby GT500, on the other hand, had a supercharged 5.2-liter V8 with 760 hp (567 kW / 771 PS) and 625 lb-ft (846 Nm) of torque.