Race-car DNA Meets Public Roads in the 2025 Porsche 963 RSP
Porsche’s latest passion project, the 2025 Porsche 963 RSP, blurs the already thin line between prototype racer and road machine. Conceived as a one-off tribute to both the legendary Count Rossi 917 and team owner Roger S. Penske, the car is essentially a re-worked LMDh 963 race car—right down to its twin-turbo V8 hybrid powertrain—yet it was coaxed onto French public roads on the eve of the 24 Hours of Le Mans. Here’s how Stuttgart, Atlanta, and Penske’s Indianapolis headquarters collaborated to re-write the rulebook, at least for one very special VIN.
Heritage: From Count Rossi to Roger Penske
The backstory is as colorful as the silver paint. In 1975, an unmodified 917—chassis 030—roared from Zuffenhausen to Paris wearing French plates and just enough concessions to satisfy the gendarmes. Half a century later, Porsche Cars North America chief Timo Resch and Porsche Motorsport brass pondered whether the current 963 could reprise that stunt. They pitched the idea to Penske, whose team fields the factory 963s in both IMSA and WEC, and the “RSP” (Roger S. Penske) project was green-lit.
Exterior: Silver, Subtle, and Purposeful
The RSP’s silhouette is familiar to anyone following the GTP grid, but closer inspection reveals numerous changes. Instead of the usual vinyl wrap, the car wears a labor-intensive Martini Silver paint—triple-layer, no less—applied over body panels so thin (a Kevlar/carbon weave) that paint adhesion is rarely attempted. Fender vents are now enclosed, echoing the 917’s smoother flanks, while a classic enamel Porsche crest replaces the race car’s flush graphic on the nose. Satin-black hinges, a 3D-printed “963 RSP” rear badge, and period-styled Michelin logos on the wet-compound rubber complete the nod to the past. License-plate mounts, of all things, sit front and rear—necessary for its short stint on public tarmac.
Cabin: Race Car Meets Lounge
Inside, the stark, Nomex-lined cockpit of a competition 963 has been civilised with tan leather and light-tone Alcantara. The fixed carbon-shell seat remains, but receives leather-trimmed cushions and retains its air-conditioning ports. The steering wheel loses its Alcantara for matching leather, a detachable 3D-printed cup-holder slots near the driver’s right knee, and ventilation bezels mimic the iconic 917’s engine-fan shape. Even the roof and A-pillars are wrapped in suede, gloving the carbon tub in surprising warmth. A plaque on the door cards lists the car’s unique chassis number and build location—just in case anyone forgets they’re sitting in a one-of-one.
Powertrain: 918 Roots, 963 Bones
The mechanical hardware stays largely faithful to what races every weekend. A 4.6-liter twin-turbo V8—derived from the RS Spyder and later the 918 Spyder—provides up to 680 hp, supplemented by a rear-axle Bosch MGU drawing from an 800-volt, 1.35 kWh battery. For road use, engineers remapped the hybrid control unit so the electric boost arrives smoothly and the car will happily sip pump premium instead of race fuel. The seven-speed Xtrac sequential gearbox remains untouched, as does the flat-plane crank that allows the engine to sit low in the chassis.
Chassis Tweaks for Tarmac
Raising a Le Mans Prototype out of race-spec stance is easier said than done, yet Multimatic DSSV dampers now sit at their softest settings and ride height is maxed out for pothole clearance. Michelin wet-compound rubber—mounted to forged OZ Racing wheels—adds flexibility for unpredictably crowned public roads. Headlight and signal programming, a functional horn, and street-legal noise levels were also baked into the software, earning the RSP a temporary French “W” manufacturer plate for its Le Mans shakedown.
Weight, Practicality, and a Hint of Skepticism
Painting over ultrathin composite panels inevitably adds grams and covering the fender vents sacrifices some aero efficiency. Purists might raise an eyebrow at the luxurious trim and even the novelty cup holder—weight is the enemy in endurance racing, after all. Yet Porsche’s engineers were adamant that nothing undermine the car’s core performance DNA. The result is a claimed curb weight barely above race trim, though Porsche declines to quote an exact figure.
Public Debut and Future Sightings
Three-time Le Mans winner Timo Bernhard handled the maiden road drive, flanking the original Count Rossi 917 for photo ops around the Circuit de la Sarthe. After its Le Mans cameo, the 963 RSP heads to the Porsche Museum in Stuttgart and will tackle the Goodwood Festival of Speed hillclimb this July. Beyond that, the car remains in Penske’s private collection; it is not, Porsche stresses, a precursor to a road-legal 963 variant.
A New Chapter in Porsche’s Sonderwunsch Program
The RSP showcases what Porsche’s revived Sonderwunsch (special wish) division can do when given a blank check and a ticking clock. While most of us will never see its bespoke Snap-On tool chest or matching carbon-shell helmet, the project hints at how much customization Porsche is willing to entertain—especially for customers with names as storied as Penske’s.
Final Lap Thoughts
By putting a full-blown GTP car on license plates, Porsche and Penske have paid homage to a 1970s rebel spirit while flexing present-day engineering muscle. The 2025 Porsche 963 RSP may never line up for a DMV inspection in Peoria, but it stands as a rolling reminder that the boundary between track and street is sometimes as thin as a layer of silver paint.
-Ed
2025 Porsche 963 RSP
