It’s been thought for some time that most German automakers like to play a little secret game where they underrate the power figures of their cars quite a bit. Having spoken to a BMW representative about this, there’s really no secret game but just a way to make sure they never accidentally overrate their power figures and get caught. Playing it safe, if you will. Still, it’s cool to see when cars actually make more power than claimed. As is the case with the new BMW Z4 M40i.
A few weeks back, Car and Driver took the Toyota Supra to a dyno and tested its power to the wheels. Turns out, it’s heavily underrated, as Toyota claims it to make 335 hp but it makes quite a bit more than that. The case seems to be similar with the BMW Z4 M40i, too.
Recently, a Z4 M40i owner took his car to get dyno tested to see just how much power it actually makes. After three separate runs, the numbers are quite interesting. As you may already know, the BMW Z4 M40i uses a 3.0 liter turbocharged I6 to make 382 hp (North American-spec) and 369 lb-ft of torque.
Turns out, it actually makes a bit less horsepower to the wheels than claimed, only putting out an average of 368 hp to the wheels, after those three runs. Though, with drivetrain loss calculated it, its claim of 382 hp is actually quite accurate at the crank. Things really get interesting when the torque was measured, though.
BMW claims the Z4 M40i makes 369 lb-ft of torque yet, after three runs, the car actually makes an average of about 414 lb-ft of torque. The peak torque figure on the three runs was 425 lb-ft. That’s a lot of torque, more than some similar diesel engines. Which would explain why the Z4 M40i is so flipping fast, especially out of corners.
So if you’re a BMW Z4 M40i owner, you now know that your car makes quite a bit more torque than advertised. So now you have some extra bragging rights at the bar with your buddies.