Lengthy earlier than Dieselgate, draconian emissions rules, and aggressive cost-cutting, Volkswagen had an period of spectacular engineering. In the course of the ruthless management of Ferdinand Piëch, there have been no limits to what the engineers may cram below the hood. The VW Group experimented with all the pieces, together with W-8 and W-12 sedans in addition to V-10 and V-12 diesel SUVs. Heck, it even made an Audi R8 with a twelve-cylinder TDI.

Beneath VW’s umbrella, Bugatti gave us the W-16 Veyron, however solely after teasing a fair wilder W-18 idea. But, the eighteen-cylinder beast wasn’t the one radical engine left on the chopping room ground. Enter the forgotten W-10. VW modified an M5 to accommodate a ten-cylinder engine earlier than BMW rolled out the E60/E61 with its naturally aspirated 5.0-liter V-10. For years, the W-10-powered M5 was nothing greater than a fantasy till the prototype surfaced on the market in 2023. Quick-forward to 2025, and Drivetribe lastly obtained the prospect to take a look at this elusive Bavarian luxurious sports activities sedan with a coronary heart transplant from a donor in Wolfsburg.

Volkswagen constructed a minimum of three W-10 engines, one in all which discovered its method right into a third-generation M5 (E39). However why? On the time, VW lacked a comparable high-performance sedan in its lineup. The unique Porsche Panamera wouldn’t arrive till 2009. Strapped to a dyno, the VW-powered M5 delivers 480 horsepower to the wheels. Factoring in drivetrain loss suggests an output of round 530 hp on the crank, a major bounce over the unique BMW S62 engine, a 4.9-liter V-8, with 394 hp. The 5.0-liter S85 that went into the M5 E60 was rated at 500 hp.

It is unclear how or why VW allowed such a novel engine, estimated to displace 5.0 liters, to finish up in personal fingers. We all know that this M5 stays rear-wheel drive with a six-speed handbook gearbox, making it an absolute riot to drive. Nevertheless, the absence of stability management and anti-lock brakes signifies that it is in all probability a handful, to say the least.

The engine was apparently a fusion of two 2.5-liter VR-5s, however not like conventional VR engines, it featured a forged aluminum block as a substitute of iron. Absolutely, Piëch will need to have had a particular automotive in thoughts when he green-lit the undertaking. Maybe one thing from Bentley? Rumor has it that VW poured €2 million into growing this M5 take a look at mule. But, regardless of the huge funding, the W-10 by no means discovered its method right into a manufacturing automotive. We’ll by no means know whether or not the engine would’ve been extra dependable than BMW’s infamous S85, which additionally powered the M6 E63/E64.

It’s believed that Piëch was so keen on the customized M5 that he used it as his private experience to work. The late VW supremo appointed Sabine (Wolfram) Willeke to guide the event staff as a part of a broader undertaking that additionally included the W-8, W-12, and W-16 engines. The German automotive conglomerate is now not making W engines. The Passat’s W-8 was retired some twenty years in the past, whereas the Continental/Flying Spur’s W-12 was discontinued in 2024. As for the Chiron’s mighty W-16, it needed to make method for Cosworth’s V-16 within the Tourbillon.