What we know!

It was back in 2023, that information was published about what many believed to be the last remaining W10 engine built by VW in the early 2000s. That engine was in the possession of a German VW mechanic who was told that the other two engines were destroyed. It is now discovered that both are part of a private collection, with one within an E39-generation BMW M5-based test mule.

This engine, part of the W range of engines, which also included the W8 that ended up in the Passat 4 Motion, the W12, found in several Volkswagen, Audi and Bentley models and the W16 that powered the Bugatti Veyron, were all developed under Piech’s watchful eye. The two additional engines, the W10, eyed for a sports sedan, and the W18, planned to be used at one point prior to the selection of the W16, were developed – yet not mass produced.

To make matters more secretive, official details about the W10-powered sport sedan are lost to history, although a recent video by “Drive Tribe” claims there was nothing like it in the VW Group’s portfolio. In what was a complicated task of putting the engine through its paces in real-world conditions, VW purchased an E39-gen M5 to use as a test mule. That engine was selected for several reasons, including its excellent handling, subtle styling and the fact that there was enough room in the engine bay to mount it.

VW spent considerable money building the one-off, W10-powered M5, and it boasted immaculate workmanship, void of any loose or hanging wires or random parts, although still a prototype.

The W10 is linked to a six-speed manual, and makes 480 horsepower and 436 lb-ft of torque at the wheels. It also sounds amazing, which is why it is such a shame that this engine never saw the production line.

Those wishing to snag the one-of-a-kind engine, in all of its big power, need to check their wallets, as it will cost about half a million dollars to add to your collection. Some may claim it’s well worth the hefty price!

This engine represented an era of impressive engineering to say the least, with the VW Group experimenting long before emissions regulations and aggressive cost cutting.

This radical engine, left on the cutting room floor, was nothing more than a myth for years until the prototype resurfaced for sale in 2023.

We do know that VW built at least three W-10 engines, one of which found its place in a third-gen M5 (E39). That vehicle delivered 480 hp to the wheels, a significant jump over the original BMW S62 engine.

What we do not know is how or why the automaker permitted such a unique engine, which was estimated to displace 5.0 liters and apparently a fusion of two 2.5 liter VR-5s, in private hands. But this long-lost engine is truly unique and with its own story to tell. A true one-of-a-kind, this experimental 10-cylinder was the engine that “could have been!”