We use cookies to remember choices you make on functionality and personal features to enhance your experience to our site. By continuing to use our site you consent to the use of cookies. Please refer to our privacy and cookie policies for more information

Skip to main content

The Audrain Concours Auction / 1995 Porsche Porsche 911 (Type 993) Supercup VIN. WP0ZZZ99ZSS398082 Engine no. 63R00134

Lot 125
Ex-Harald Grohs
1995 Porsche 911 (Type 993) Supercup
30 September 2022, 16:00 EDT
Newport, Rhode Island, International Tennis Hall of Fame

US$350,000 - US$400,000

Ask about this lot

1995 Porsche 911 (Type 993) Supercup
VIN. WP0ZZZ99ZSS398082
Engine no. 63R00134

3.8L Air-cooled Flat 6-Cylinder Engine (M64/70)
Electronic Fuel Injection
310bhp at 6,100rpm
6-Speed Reinforced Manual Gearbox (G50/30)
4-Wheel Independent Suspension
4-Wheel Disc Brakes

*Rare factory-built 993 Supercup
*Full chassis / body-off restoration
*Ever growing collectability
*Sounds as great as it looks


In 1993, Porsche introduced what is regarded by many as the most beautiful 911 of all—the Type 993. Over the years, the 911 had received numerous aerodynamic and safety-inspired add-ons, diluting the purity of the original form. The Type 993's arrival marked a return to basic principles, being recognizably a 911, but one in which all functions had been harmoniously integrated in a truly outstanding example of modern automotive styling. The 993-range offering was comprised of the familiar two- and four-wheel drive models, a Cabriolet convertible, the Turbo, but also included the new range topping 1997 993 Turbo S. All were powered by the latest, 3.6-liter version of Porsche's perennial flat-six engine.

Other than the 'road-legal' models, Porsche also started to work on the race-only version of the 993 to replace the 964 Cup, and thus renew their two 911-only Championships, the Carrera Cup (German) and Supercup that basically followed Formula 1 Grand Prix as opening races from 1993 to 1998. Under the supervision of Roland Kußmaul at the Porsche Racing Department, the development of the 'Cup' 993 began around mid-1993, even before the official presentation of the new generation. Unlike the 964 Cup that was basically a race-prepped road car, the 993 was a more serious deviation from the road models, especially through the use of the 3.8L engine – M64/70 – inherited from the 964 RS, unlike the rest of the pack with their 3.6L. The engine was developed under Herbert Ampferer supervision, and achieved 310hp at 6,100rpm. Interestingly enough, while the rev-limiter was set at 6,900rpm, that practically identical engine could safely run at 7,900rpm in the RSR, which allowed for a high performance, yet highly reliable usage for competition being somehow under-stressed. The gearbox was shortened and reinforced compared to the series version, especially with the use of synchronous rings made of steel.

"The new multi-link rear axle in the series-production Porsche comes very close to a double-wishbone construction. We trimmed it to make it even more like a racing suspension. The car is 70 mm lower than the production counterpart, the spring rate is twice as hard as last year's Cup car, and, in cooperation with Pirelli, we've achieved a handling performance that even the most demanding of racers have praised as sensational." Roland Kußmaul, Porsche Sport '94.

Through a series or weight-trimming measures, the 993 Cup ended up at 1,100kg (2,425lbs); the roll cage and work on the body rigidity allowed for extra safety and solidity in case of a crash, while the braking was made of high-performance ventilated discs stopped by four-piston calipers.
The 993 Cup was used in the Supercup starting in 1993, while the Carrera Cup still used the 964 Cup, which changed in 1995 with the adoption of the 993 for both Championships. 1995 is also the year where the Cup would receive its final 'body version' with the adoption of the aero from the newly developed Carrera RS Clubsport, comprehending notably a larger front spoiler and sill trims.

In total, 216 993 Cups exited the Weissach factory, 147 with the 310bhp engine and 69 with the 315bhp (post-1996), before the transition to 996 GT3 Cup for the 1998 season.


Following the copy of the ONS Wagenpaß, number 1856/95, it appears that this 993 Supercup exited the Weissach factory on April 4th, 1995. Looking at the pictures on file, it seems that the car got delivered to renown German Porsche specialist, Probst Motorsport.
Based on oral history, the car would have been raced by 1995 Carrera Cup Champion, Harald Grohs, using the car under number 25 through the 1996 and 1997 Supercup Championship.

Thanks to a bill of sale on file, we learn that the car has then been sold on September 25th, 1997, from Classic Automobielen Zuid Nederland to notorious Porsche afficionados and racers Franco and Giovanni Natale out of Baltimore, MD. The car has then been modified and stripped down from its Supercup body kits to receive GT2 aero, got its engine modified to produce about 370hp and used on PCA races. Pictures of the Franco brothers' showroom notably shows the other Grohs' car from the time, number 3, next to its sister with its new GT2 look.

The current caretaker of the car purchased it directly from the Franco brothers back in 2005, while the car was obviously fatigued from about 20 straight years of hard racing. As a true Porsche enthusiast, and avid racer, the owner undertook a precise and lengthy full chassis / body-off restoration to bring the car back to its out-of-Weissach condition with Grohs' number 25 livery it shows today. A large folder is on file showing pictures of the whole restoration process, as well as the invoice for the engine rebuilt, made by Porsche renown mechanic, Pat Williams from Memphis, TN, reaching an amount close to $20,000. The engine was rebuilt to the exact factory 3.8L specs, to finalize the process of bringing back to the car to its original stage. No cost was spared through the process, with any part needing replacement - whether they would be for the engine, body or chassis – being done through official Porsche parts.

With only 216 examples produced, and considering the way those were raced, finding these 993 Supercup has become more and more challenging, which naturally participates to their desirability and future high collectability. The present car goes to show the dedication of its current owner to bring the car back to its original look and specs and appears today as a staggering window to when these beautiful machines were actually taken as race cars and not collectible pieces. This Supercup will find its place in a private Porsche collection, in a museum or in its natural habitat, on tracks, and surely bring its new keeper a great load on enjoyment.



Additional information