It has not been yet confirmed with multiple sources, but the rumor mill has it that BMW is developing a tri-turbo diesel engine based on the six-cylinder turbo existing in the BMW line-up. The tri-turbo engine will output 354 horsepower and it will be initially used in a BMW X5 Performance Diesel.
This new engine will carry the EfficientDynamics badge by incorporating technologies like Start-Stop system and Brake Energy Regeneration (KERS). It will be geared towards the European market in need for a top X5 model.
BMW X5 Performance Diesel has less pronounced wheel arches that the ones seen on the new BMW X5 M . The Wheels give the car very sporting and powerful appearance. The aerodynamic performance package follows the design of the X5 M, but the central intake is smaller with the intakes for the brakes less open mouthed and a colored bar across .
Same source, someone close to BMW, speaks of subtle spoilers for air flow at the leading edge of the bumper. The rear of the car features two larger and more exposed performance exhaust pipes which will be incorporated in the upcoming facelift of the X5.
The tri-turbo engine will be first available in the X5 models and the X6 at a later date. BMW plans to introduce the engine within key models such as the next 5 Series , 7 Series and eventually the additional 5er and 6er variants.
It is unknown what name will these X5 models carry, but as soon as we get more info, you’ll have it.[Source: Scott27 ]