Fat Fender Garage Unveils 800-HP Ford F-100 After 15,000-Hour Build

More than 15,000 hours of design, engineering and fabrication went into turning a 1956 Ford F-100 into the GT/FX, an 800-horsepower restomod built to carry the power and attitude of a modern Mustang GT. Arizona-based Fat Fender Garage unveiled the one-off truck at SEMA in Las Vegas.

That labor figure reflects a project extending well beyond an engine swap or cosmetic restoration. The builder installed a modern supercharged Ford powertrain, placed the pickup on a dedicated performance chassis and extensively reshaped its all-steel body by hand. The result retains the recognizable grille and general identity of a 1956 F-100, but little of the original vehicle’s underlying engineering remains untouched.

A supercharged Ford V8 supplies the stated 800 horsepower

The GT/FX uses a third-generation Ford 5.0-liter Coyote V8 fitted with a 3.0-liter Whipple supercharger. Fat Fender Garage states that the combination produces 800 horsepower and 750 pound-feet of torque. Those are builder-provided output figures rather than independently verified performance results.

Supercharging is the central mechanical step behind that output. The engine-driven compressor forces more air into the V8, allowing it to burn more fuel and produce substantially more power than the naturally aspirated engine. That additional airflow and combustion load make the powertrain installation more involved than simply placing a newer V8 between old frame rails.

Power runs through Ford’s 10R80 10-speed automatic transmission. Its broad ratio spread gives the engine more opportunities to operate in a useful speed range than the transmissions available when the F-100 was new. The truck also has a custom three-inch exhaust incorporating Borla XR-1 Raceline mufflers, JMD resonators and electric cutouts.

The body consumed extensive hand-fabrication

Fat Fender Garage retained steel construction but changed the body’s proportions and surfaces throughout. The roof and hood were pancaked, the cab was sectioned by two inches, and both the front and rear fenders were widened. Custom running boards connect those altered forms, while flush-mounted front and rear glass and one-piece side windows further separate the truck from a conventional restoration.

The original grille is described as the only major exterior component that remained unmodified. That detail illustrates the project’s basic tension: the GT/FX needed to remain identifiable as a 1956 Ford pickup even as its dimensions, aerodynamic elements and finish moved toward a modern performance car.

Mustang influence appears most explicitly at the rear, where the builder grafted in a Ford Mustang Shelby GT350 diffuser. A bespoke front air scoop and chin splitters carry that performance theme forward. The double-walled bed received distinctive flares and a push-button tailgate, while carbon-fiber mirrors and custom LED taillights add modern materials and lighting.

A performance chassis replaces the old-truck foundation

Underneath, the GT/FX uses Fat Fender Garage’s FF1 Performance Coilover Chassis. The company says the platform is intended to give the classic pickup modern handling characteristics. Coilovers provide a contemporary spring-and-damper arrangement, but the available information does not include instrumented handling, braking or acceleration results.

Custom HRE wheels wear Toyo Proxes Sport 2 tires. Wider modern performance tires are a necessary companion to the stated engine output and performance-chassis objective because the powertrain can only accelerate, turn or stop the truck through the available tire contact patches. The combination also helps accommodate the pickup’s widened fenders and altered stance.

Inside, leather-trimmed bucket seats replace the basic seating associated with a period truck. Modern gauges and audio equipment are integrated with custom door actuators and a concealed climate-control system. Hiding that equipment supports the larger design approach: adding current functionality without letting every modern component visually overwhelm the 1956 body.

Fat Fender Garage has not announced a price for the GT/FX. As a one-off SEMA build with more than 15,000 hours invested, its defining number is therefore labor rather than cost a measure of how much engineering and hand-fabrication were required to make an old F-100 carry an 800-horsepower supercharged Ford V8 while still looking unmistakably like a 1956 pickup.

By Robert McKinney — Editor-in-Chief for AMI’s automotive and mobility coverage, with a mechanical engineering background and a decade reporting on powertrain systems, EV innovation, and global vehicle manufacturing.