Volkswagen’s experimental W10 engine sits in a unique BMW M5 E39 now heading to auction, with experts expecting it to fetch between 250,000 and 350,000 euros. Ferdinand Piëch, grandson of Porsche’s founder and a force behind modern supercars, ordered the secret project and drove the car during development.
Broad Arrow Auctions will offer the one-off at the Zoute Concours Auction in Knokke-Heist, Belgium, on October 9, 2026, several independent automotive publications report. Its significance goes beyond its story: it is the only road car ever built with Volkswagen’s experimental naturally aspirated W10 engine. Only three of these engines exist.
In 1999, Volkswagen engineers faced a problem: they had built a radical W10 engine, but none of their own cars could accommodate it. They bought a BMW M5 E39, removed its original S62 V8 and installed the all-aluminum 5.0-liter W10. The engine produced between 473 and 480 horsepower and about 592 to 593 Nm of torque, as detailed in auction documents and independent sources. Compared with the stock M5, the car gained large power and torque while adding just 11 kilograms.
This was not an official Volkswagen R&D project. It was conducted off the books, with a reported budget of around 2 million euros. Piëch liked the result enough to lead the car himself during development. Auction listings and automotive historians report that only three W10 engines were built: one remains in Germany, another will be displayed with the M5 at auction, and the third is in the car.
Volkswagen engineers used a production BMW M5 E39 chassis instead of building a new prototype from scratch. They retained rear-wheel lead and the six-speed manual transmission, letting them test the W10 in real-world conditions. Industry analysts have noted that the approach was unusual.
The W10 grew out of Volkswagen’s earlier engine experiments. The VR6, launched in 1991, began a new era for W-shaped engines. Its compact design led to the W8 and W12, which powered the Passat and Phaeton. The W10 proved unsuitable for mass production and remained a prototype. By combining two VR5 units, Volkswagen created a stepping stone toward the W16, which would later power the Bugatti Veyron and Chiron.
The BMW M5 E39 W10 was never approved for road use. It remains the only road car built with a Volkswagen W10 engine. Broad Arrow Auctions will offer it on October 9, giving collectors a rare chance to own a car that connects BMW and Volkswagen to Bugatti.
As reported earlier, vehicles with one-of-a-kind stories continue to draw crowds and earn respect from collectors and enthusiasts.
Volkswagen dropped the W10 from its production-car plans and chose the W12 for models such as the Audi A8 and Volkswagen Touareg. That decision cleared the path for the W16’s debut in the Bugatti Veyron.
