Broad Arrow Will Auction Unique VW-Powered BMW M5
A rare E39-generation BMW M5 prototype featuring a custom 5.0-liter W10 engine will head to auction on October 9.
Updated on Oct. 5, 2026 in Performance Vehicles
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Broad Arrow Auctions will offer a rare E39-generation BMW M5 prototype fitted with a Volkswagen-developed W10 engine. Once used as a personal vehicle by Ferdinand Piëch, the car is expected to sell for between €250,000 and €350,000 on October 9.
Why it matters
The vehicle showcases an experimental engineering phase where Volkswagen sought an engine more specialized than a standard V8. This prototype served as a critical testbed, directly influencing the eventual development of the automaker's iconic W12 and W16 engine platforms.
The prototype features a 5.0-liter naturally aspirated W10 engine producing 480 hp and 437 lb-ft of torque. Only three such engines were ever built, making this the only road-legal example currently in existence.
The players
Broad Arrow Auctions
Broad Arrow Auctions is an entity facilitating the high-end sale of this unique automotive prototype.
Ferdinand Piëch
Ferdinand Piëch was a prominent automotive executive who utilized this specific prototype as his personal vehicle.
Volkswagen
Volkswagen is a global automotive manufacturer that invested in the development of the W10, W12, and W16 engine architectures.
The details
Volkswagen acquired the E39 M5 in 1999 to house a new engine created by combining two 2.5-liter VR5 units. The vehicle remains equipped with its original six-speed manual transmission and rear-wheel drive configuration.
Timeline
1999: Volkswagen acquired the BMW M5 for engine development.
October 9, 2026: Broad Arrow Auctions will sell the vehicle.
Roadmap
This prototype represents the experimental engineering era that bridged the gap between basic engine designs and modern high-performance configurations. The W10 design served as a foundational step for the company's subsequent W12 and W16 engine platforms.
This auction provides a rare opportunity for collectors to acquire a unique piece of automotive engineering history. Prospective buyers should prepare for high-level maintenance requirements given the custom nature of the W10 engine.
The takeaway
This sale highlights how manufacturers often use donor vehicles from rival brands to test proprietary engine concepts in real-world conditions. Prospective high-end vehicle collectors should always account for the specialized service needs of one-off prototype vehicles.
Further reading
Explore more history and listings in our Performance Vehicles section.
Source note: This article includes information reported by Carscoops.
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