Overview
- Porsche built the Flachbau RS as a private, factory‑backed one‑off commissioned by a collector and presented the project publicly this week.
- The three‑year development program was led by Sonderwunsch and Porsche design with Grant Larson as the design lead and Manthey contributing the aero work.
- Porsche retained the donor car’s 3.8‑litre twin‑turbo flat‑six, quoted at about 515 kW and 750 Nm, mated to the original seven‑speed dual‑clutch gearbox so powertrain and driveline were unchanged.
- A new Manthey aero package adds a three‑position rear wing that produces up to 554 kg of rear downforce in its high position and was validated by wind‑tunnel, static load tests and at least 50 Nürburgring laps.
- Porsche removed infotainment, sound deadening, carpets and excess wiring to save 31.6 kg, kept full safety systems and crash testing, and confirmed the Flachbau name was registered in 2025 as part of Sonderwunsch’s growing bespoke programme.