BMW’s have always performed well on dynos. Every time a new BMW launches, enthusiasts put their cars on dyno machines to test their real power figures and they’re always more than what BMW claims. However, that phenomenon isn’t unique to BMW. Almost all German manufacturers underrate their power figures. And since they all use such similarly size/powered engines, which one actually has the most power? In this new video from Carwow, Mat Watson puts the BMW M5 on a dyno, alongside its competitors, to find out.

The BMW M5 Competition is one of the most powerful sedans on the planet, with its 4.4-liter twin-turbo V8 making 617 claimed horsepower and 553 lb-ft of torque. However, it’s far from the only powerful V8-powered German sedan in the segment. The Audi RS6 Avant makes a claimed 600 horsepower and 590 lb-ft. Mercedes’ AMG E63 makes 603 horsepower and 627 lb-ft, according to its spec sheet. And lastly, the Porsche Panamera Turbo S E-Hybrid is said to make 690 horsepower and 642 lb-ft. But the dyno reveals all, so who makes the most power?

When it was the BMW M5’s turn to reveal its true power, it actually put out quite a bit more power than claimed. According to the dyno, it made 651 horsepower and an astonishing 863 Nm (636 lb-ft) of torque. That horsepower figure is impressive but it’s the torque figure that boggles the mind. Why does BMW advertise 553 lb-ft when it makes almost 100 lb-ft more? That’s not just underrating, that’s flat-out bluffing.

What about weight, though? Is BMW honest about the M5’s diet? According to BMW, the M5 Competition weighs 1,940 kg (4,277 lbs). When Watson and crew put it on the scales, it weighed 1,928 kg (4,251 lbs). So really close but actually a bit lighter than claimed. At over two-tons, 26 lbs really doesn’t matter much and won’t make a difference in performance or feel. However, it’s real power-to-weight ratio is completely different than the claimed one and BMW seems to be trying to hustle its competition by claiming far worse figures than it actually has.

How about the other cars in the test? You’re going to have to watch the video to find that out but, if you don’t want to watch (or can’t watch), just know that BMW is a lying about its power. In a good way.