The final chapter of Gunther Werks’ Speedster program has arrived with a one-off creation that unapologetically channels Tony Stark’s alter ego. Called Project Endgame, the vehicle is the first in the line to feature an air-cooled turbocharged engine, developed by Rothsport Racing and delivering 626kW — equivalent to 840 horsepower — and 895Nm of torque from a 4.0-litre twin-turbo flat-six.
Built on a heavily modified Porsche 993 platform, the car combines extreme engineering with deliberate theatricality. Its carbon fibre bodywork replaces the traditional ducktail with a large fixed rear wing, although reworked bumpers, enlarged air intakes and a prominent diffuser reinforce a purposeful stance. Despite the added hardware, the vehicle weighs just over 1179kg, maintaining a supercar-level power-to-mass ratio.
The design leans into its superhero inspiration without reservation. Finished in deep candy red with gold accents on mirrors, headlights and badging, the interior continues the theme: a bespoke gear shifter features 24-karat gold and coloured stones representing each of the six gears, a direct nod to the Infinity Stones. Carbon-backed seats trimmed in red and black leather, along with further gold detailing, complete a cabin that reads more as a statement than a functional space.
This level of extravagance is intentional. Gunther Werks has not sought to temper the build for its final offering; instead, it doubles down on the core tenets that defined the brand — power, craftsmanship and a willingness to exceed conventional limits. As Peter Nam, CEO and founder, stated, every element was precision-engineered in close collaboration with the client, with performance as the paramount directive.
The air-cooled setup marks a technical first for the Speedster line. A flat-fan system manages cylinder cooling, while the air-to-water intercoolers are wrapped in 24-karat gold — a detail underscoring the absence of restraint at this level. Power is transmitted via a six-speed manual gearbox with bespoke ratios, preserving an analogue driving experience despite the extraordinary output.
Though Gunther Werks had originally planned for only 25 open-top variants in its Speedster program — which technically concluded in 2023 — Project Endgame exists as a singular exception. It will remain the only open-top version of the GW Turbo, a model slated for 75 units but distinguished by this unique configuration.
The vehicle will make its public debut at the Air|Water event in Costa Mesa on April 25, 2026, before being displayed exclusively at a museum operated by the Natsukashii Foundation. For observers, it represents not just the end of a program, but the culmination of nearly a decade of refinement distilled into one extreme expression of the marque’s ethos.
How the build reflects the client’s identity
The vehicle’s design choices leave little ambiguity about its inspiration. From the candy red and gold paint scheme to the gem-adorned gear shifter mirroring the Infinity Stones, every visual cue aligns with the Marvel character Iron Man. Even the project’s name, Endgame, serves as a narrative echo, referencing the 2019 film in which Tony Stark sacrifices himself to save the universe.
What this means for the GW Turbo line
While 75 GW Turbos are planned for production, Project Endgame will be the sole open-top variant among them. This distinction ensures its uniqueness within a limited run, reinforcing its status as a one-off commissioned piece rather than a precursor to future models.
What makes the engine in Project Endgame unique?
It is the first air-cooled turbocharged engine used in a Gunther Werks Speedster, developed by Rothsport Racing and delivering 626kW and 895Nm of torque.
Where will the car be shown after its debut?
Following its public debut at the Air|Water event in Costa Mesa on April 25, 2026, it will be exclusively displayed at a museum operated by the Natsukashii Foundation.