RTR just unleashed its most ambitious Mustang build yet, and the numbers are genuinely impressive. The Spec 5 transforms a regular Mustang GT into an 870+ horsepower monster for $160,000, creating supercar performance at Porsche 911 Turbo S money.
The foundation starts with the familiar 5.0-liter Coyote V8, but RTR adds a 3.0-liter Whipple Stage 2 supercharger, HD Race intercooler system, and Borla cat-back exhaust. Output jumps to 870+ horsepower and 660 lb-ft of torque, surpassing Ford’s own track-focused GTD by 55 horsepower despite costing significantly less.
That pricing includes the base Mustang GT with Performance Package, making the math more palatable than it initially appears. The Spec 5 also undercuts the 830hp Shelby Super Snake by over $10,000, positioning it between aftermarket tuner builds and factory extreme machines.
RTR’s tactical performance suspension brings serious hardware, including 30-way adjustable front coilovers and rear dampers, height-adjustable springs, and adjustable sway bars front and rear. The system maintains suspension articulation despite the lowered stance, crucial for actually using that massive power output.
The widebody kit represents RTR’s first complete exterior transformation, featuring composite front and rear fenders with integrated cooling vents, rocker panels, and bumper extensions. Carbon fiber components include the front splitter, side skirts, and wake towers that provide genuine aerodynamic function alongside aggressive styling.
Michelin Pilot Sport 4S tires wrap 20-inch forged RTR Aero 5 Evo wheels measuring 10.5 inches front and 11 inches rear. Six-piston Brembo calipers with two-piece rotors up front provide stopping power to match the acceleration potential.
Inside, Recaro sport seats feature cool grey leather bolsters with black suede centers and ribbed inserts. Each car gets an electronic drift brake, serialized dash plaque with Vaughn Gittin Jr’s signature, and RTR performance shift knob. Buyers can choose between a six-speed manual transmission or a ten-speed automatic transmission.
Production caps at 50 units for 2026, ensuring exclusivity for buyers willing to spend serious money on domestic muscle. The Spec 5 demonstrates how aftermarket specialists can exceed factory performance benchmarks through focused engineering and premium components.
RTR’s pricing strategy makes sense when considering alternatives. Comparable European performance costs significantly more, making the Spec 5 a compelling proposition for buyers seeking maximum horsepower per dollar in limited production form.
The upward-opening fuel door might seem trivial, but RTR’s attention to details like billet aluminum arms and integrated drainage systems shows commitment to execution beyond just power gains.
