Porsche 928 S4 Clubsport

The vehicle in detail

Chassis No. WP0ZZZ92ZHS841983
Porsche Internal No. H54

Few drivers of his era combined Formula One pedigree with endurance racing success as convincingly as Jochen Mass. A Grand Prix winner with McLaren in 1975 and one of the most accomplished German drivers prior to the Schumacher era, Mass built his reputation on pure speed, consistency, and intelligence. After his years in Formula One, the avid sailor and adventurer became a mainstay of Porsche’s factory effort from 1976 through 1987, playing a key role in the marque’s dominant Group C program and regularly campaigning the 956 and 962 at the highest levels of international sports car racing.

It was during this period, at the height of the 962 program, that Porsche developed a small run of lightweight 928 Clubsport prototypes, built a year ahead of the model’s public debut. The standard 928 was reworked with a clear focus on weight reduction and driver engagement, adopting a lighter five-speed dog-leg manual transaxle, stiffer suspension, and engine revisions for improved response. Comfort equipment was pared back throughout, resulting in a weight savings of an impressive 300 pounds! Just four pre-production examples were produced, each in classic Grand Prix White over a Marine Blue leather interior. For the maximum publicity benefit and to further the development of the production car, each was assigned to a Rothmans Porsche 962 works driver—Jochen Mass, Derek Bell, Hans-Joachim Stuck, and Bob Wollek—as high-speed personal transport between races.

Jochen Mass would be the first to receive his, designated internally as H54. No doubt the 928’s white and blue livery appealed to Mass’ nautical interests! Interestingly, the substantial history file chronicling Mass’ 928 Clubsport begins earlier than the production of the chassis itself. A document from the West German Kraftfahrt-Bundesamt (Federal Motor Transport Authority) is on file approving Porsche’s request to operate Mass’ Clubsport prototype on Böblingen license plates (BB-PN 269) for a two-year period with the request that the approval paperwork remain within the car at all times.

928 Clubsport H54’s service book reveals that while initially held by Porsche, entry information records (beneath correction fluid) that it was also under Mass’ stewardship. Mass’ information was also added in a lower section along with his indelible signature on the second page. A copy of the Fahrzeugbrief shows that, following its time with Porsche, Jochen Mass retained the Grand Prix White Clubsport registered by 1993 on Rhein-Neckar-Kreis number plates and under Mass’ wife’s name, Bettina Dunne. During Jochen Mass’ ownership, the future 1989 24 Hours of Le Mans winner accumulated over 76,000 kilometers, representing the vast majority of the car’s total 109,321 km.

After Mass parted with his lightweight 928 Clubsport after 11 years of ownership, it was acquired by Roland Mews of Landau, just southwest of Stuttgart, in 1998. Mews retained the car until 2006 when it was purchased by Jørn Jakobsen and registered on Kiel number plates before relocating to Norway. Most importantly, the documented link to its original owner—Formula One race winner Jochen Mass—remained intact. In 2014, the 928 CS was purchased by the consignor as an early acquisition into a collection of rare and exclusive Porsche vehicles known for their collectible interest and “one-off” nature. As the first of just four 928 Clubsport prototypes produced, it was certainly an astute acquisition. First located in Switzerland, it was later brought to southern California in 2023.

At the time of cataloging, Jochen Mass’ former factory 928 Clubsport development prototype features 109,321 km (c. 67,929 miles) from new and is offered for the first time to the public in excellent condition in advance of Broad Arrow’s debut sale at The Quail. Furthermore, the lightweight 928 is furnished with its original manuals and service book signed by Jochen Mass, Porsche registration and service paperwork, and a signed Personal Edition copy of Jochen Mass’ biography by Peter Schroeder, among other desirable items from the F1 and endurance racer’s time with the car.