While Porsche is preparing for the 24 Hours of Le Mans with the 963, among other things, the sports car manufacturer today presented a one-off production of the hypercar: the 963 RSP.

Based on the winner of the IMSA and WEC racing series, the vehicle was inspired by a very special Porsche 917. A 917 that was completed 50 years ago. Fittingly, the 963 RSP celebrated its premiere today on the roads near the Circuit de la Sarthe – with its ancestor.

A special trip: From Zuffenhausen to Paris

In April 1975, a Porsche 917 (chassis number 30) – probably the most modern endurance racing car of its time – undertook a very special drive: not to the race track, but on public roads. From Zuffenhausen they went to Paris. The owner at the time, Count Rossi, wanted as few changes as necessary to make the car roadworthy. The sports car is still driven today, it can be seen occasionally in France.

"The whole thing started with the question: 'What if?' A project driven by the passion of a small team full of enthusiasts from Penske and Porsche, who together had in mind a version of the 963 that was as close as possible to the spirit and appearance of the Count Rossi 917," said Porsche Cars North America President and CEO Timo Resch, who presented the idea for the project for the first time. "The 917 was a race car through and through – albeit one that raced on the public road – and we implemented this approach with the 963 RSP as well. It is made of high-quality materials and is still a pure racing car at its core."

A team of employees from Porsche AG, Porsche Penske Motorsport and Porsche Cars North America brought the car to life together with motorsport legend Roger Penske, whose initials "RSP" inspired the naming. The 963 RSP has been extensively modified compared to its original version. Unlike vehicles intended for racing and covered with colourful foiling, the 963 RSP is the first vehicle of its kind to be completely painted.

Since the body is made of carbon and Kevlar® and is particularly thin in terms of weight minimization, this posed a particular challenge for the painters. As a tribute to the Count Rossi 917, the 963 RSP was painted in Martini Silver. In addition, the one-off is characterised by adapted body parts and a refined interior with light brown leather and Alcantara, inspired by the materials that Count Rossi selected for his 917 50 years ago.

For the world premiere on the roads near Le Mans, the ground clearance was maximized. In addition, the dampers have a special set-up and the headlights and taillights have been adapted for use on the road. Together with the trim of the wheel arch shells, Michelin rain tyres and even a horn, the 963 RSP thus meets the requirements of the French authorities and can be driven on public roads with license plates and special approval – supported by the Automobile Club de l'Ouest (ACO).

"That was an experience that will stay with me for a lifetime," said Timo Bernhard, who drove the first few kilometres on the road with the 963 RSP. "Driving this vehicle on a public road and a 917 next to me – it felt unreal. The car behaved perfectly – it seemed a little friendlier and more forgiving than the normal 963 – and felt super special and much more comfortable, especially because I didn't have to wear all the safety equipment."

Roger Penske, Chairman of the Board of Directors of Penske Corporation, says of the project: "We have a great connection with Porsche that dates back to 1972. With numerous victories and championships – especially Mark Donohue's high-speed record in 1975 – the Porsche 917/30 represents a very special era in the history of Team Penske. This important partnership continues today. So it was time to create the most exciting car we could imagine. Like the Count Rossi 917, I wanted this car to stay true to its starting point and get as few changes as possible. When we started the project, the difference between the two race cars from different generations was a big challenge. The end result is a vehicle that has lost none of its purist character and inspires both on the race track and on the road."

The 963 will be on display at the Circuit de la Sarthe during the 24 Hours of Le Mans before heading to the Porsche Museum in Stuttgart. In July, the car will be on display alongside its ancestor, the 917, at the Goodwood Festival of Speed.

The "963 RSP" project in detail

The concept was originally launched during a meeting at the Road Atlanta racetrack between Timo Resch, President and CEO of Porsche Cars North America, Thomas Laudenbach, Vice President Porsche Motorsport, and Urs Kuratle, Vice President Factory Motorsport LMDh. Inspired by the Count Rossi 917, she wanted to repeat this approach with a 963. Roger Penske and Jonathan Diuguid, Executive Director Porsche Penske Motorsport, endorsed the project and further developed the concept. Roger Penske was chosen as the future owner of the car and the RSP suffix was chosen in his honor.

Design Process: Exterior

After the concept was defined, the Sonderwunsch team in Zuffenhausen began to turn the idea into reality. They were supported by Sonderwunsch colleagues from the Porsche Classic team in Atlanta. Based on the changes selected by Count Rossi in 1975, Grant Larson, Head of Special Projects Design, and his team drew a 963 that was as close to the original as possible. A silver paint with black accents was used for the exterior, while the interior was to receive a combination of light brown leather and Alcantara. Like the original, the 963 was to be painted and not foiled, which posed a particular challenge due to the body construction consisting of carbon and Kevlar®. The paint-to-sample paint "Martini Silver" has been verified by the Porsche Museum in Stuttgart-Zuffenhausen using historical documents.

Smaller body parts such as door hinges and wing joints were finished in velvet black. At the rear, a 3D-printed '963 RSP' lettering identifies the unique piece.

To match the body details of the 917, changes were made to the body of the 963 RSP. A special detail: the custom-made ventilation grilles for the wheel arches, which are usually open on the racing version. The ventilation grilles were initially developed virtually by Porsche Sonderwunsch and Porsche Penske Motorsport and then manufactured. The new design still allows effective ventilation of the wheel arches. In addition, the carbon cover plate, which is usually located in the rear wing according to the racing regulations, was removed from the 963 RSP. At the front, an enamelled Porsche crest replaces the sticker usually attached to the racing car. Another detail that connects 917 and 963 RSP.

The forged 18-inch OZ Racing rims were fitted with Michelin rain tires. On the flanks of the tires you can see historic Michelin lettering in the style of the 1970s. Another novelty: attachment points for license plates were installed in order to be able to move the vehicle on public roads and to be able to celebrate the 50th anniversary of the 917's first road trip in a fitting manner.

Design Process: Interior

Probably the biggest difference to the 963 racing car can be found in the interior of the 963 RSP. Inspired by the special interior of the 917, the 963 RSP offers a combination of soft, tan leather and Alcantara. While the racing car offers little comfort, the 963 RSP shows more accommodation. The one-piece carbon seat for the driver has been covered in leather and has an upholstered seat centre panel and a headrest that is firmly attached to the bulkhead. As with the racing version, the seat is air-conditioned. The leg rests as well as the headliner and the A-pillars are covered with Alcantara. The steering wheel, which is used to operate most functions in the car, is covered in leather. Nice detail: A removable, 3D-printed cup holder reliably holds a Porsche thermo mug.

To the right of the driver's seat, a newly created cushion allows a headset and the steering wheel to be accommodated when the vehicle is not being moved. There is also room for the laptop needed to start and operate the vehicle, as well as the individualized racing helmet, which was specially made for Roger Penske.

While the color choice of the interior is clearly based on the 917, there are also more subtle hints of the ancestor. These include custom-made end plates for the air vents, the design of which was inspired by the fan of the 917's 12-cylinder engine. The doors have been upholstered in leather and Alcantara on the inside, and a small metal plaque in the driver's door shows the chassis number and the location of the car. For the best possible road performance, the ground clearance has been raised to the maximum level, while the adjustable Multimatic DSSV dampers are softer tuned to increase driving comfort. The vehicle's control units have been programmed to enable a side turn signal function and to optimize the headlights for road use.

The V8 hybrid with lithium-ion battery – which also realizes purely electric propulsion – remained mechanically untouched, but the MGU's power delivery was electronically optimized for road driving. The engine was also tuned to run on conventional fuel – a major challenge for the team.

The final touches

The 963 RSP comes with a special racing helmet that is painted in Martini Silver accents to match the vehicle. In addition, the car comes with a snap-on toolbox, which is also equipped with matching color accents, a plaque and leather handles. The drawers are equipped with specially shaped foam and provide space for the tools needed to operate the vehicle.

While the 963 RSP was allowed to make its world premiere on local roads near Le Mans thanks to its modifications in accordance with local regulations with special approval and the use of French "W" license plates, it is not a completely street-legal vehicle, and will remain a one-off.

The drive of the 963

The 963 is powered by a 4.6 liter V8 biturbo engine, which develops about 680 hp and comes from the RS Spyder racing program. With this, Penske won all titles in the LMP2 class of the American Le Mans Series from 2006 to 2008. The engine was enlarged from 3.4 to 4.6 litres for use in the 918 Spyder. The flat crankshaft and short stroke of the engine allow for a very low installation, which benefits the vehicle's centre of gravity. While the 918 Spyder used a naturally aspirated engine design, the 963 was fitted with two turbochargers from the Dutch manufacturer Van der Lee. These turbochargers generate very moderate boost pressure and are housed on the hot side of the engine, which optimizes throttle response. Overall, around 80 per cent of the engine parts in the 963 are identical to those of the 918 Spyder, which was already designed for the use of a hybrid system.

The standardized components of the hybrid drive are contributed by Bosch (motor generator, electronics, and software) and Williams Advanced Engineering (high-voltage battery). The electric motor (MGU), which is responsible for power delivery and recuperation when braking on the rear axle, works directly with Xtrac's seven-speed sequential transmission. The MGU is housed between the V8 engine and the transmission.

The electric system of the hybrid drive operates at up to 800 volts. The battery has a capacity of 1.35 kWh, which can be used at any time during acceleration phases. A power output of 30 to 50 kW is available for a short time, but does not change the system output of the drive. When the MGU is activated, the power of the engine, which reaches up to 8,000 rpm (depending on the BOP), is automatically reduced.

From the racetrack to the road: The Porsche 963 RSP