BMW says that the twin-turbo inline six in their new 2015 BMW M3 has 425 horsepower. But those in the know, and those who have driven it, swear it's underrated. Now we know the truth.

The folks at European Auto Source recently strapped a DCT-equipped 2015 M3 owned by Josh of Speed District to the Dynojet and took it for a spin. Lo and behold: 424 horsepower, 425 pound-feet of torque.

The True Power Of The 2015 BMW M3 Revealed In Dyno Run

And of course, that's just at the wheels. Assuming a minimum of 10 percent drivetrain loss, that means the new M3 has something like 460 horsepower or more at the crank.

Well done, BMW. This new car ain't messing around.

Hat tip to Carscoops!