When it comes to the BMW mythos there are not fewer more prized models than the 1972 2002 Turbo. Produced for only one year with 1672 cars created it showed what performance BMW could muster out of forced induction. BMW fans were again teased in the 80s with the 745i, but it would be another 26 years before Munich bolted a turbocharger to its engines again. The BMW 135 6-Cyl. Twin Turbo engine is the culmination of all the company has learned from its long history of creating naturally aspirated inline sixes and turbocharging technology used in its ground breaking diesel vehicles.
The BMW 135 6-Cyl. Twin Turbo Engine codenamed the N55 replaces the previous generation N54 that debuted in 2006. The current twin turbo engine first saw action in 2009 in the 5-Series GT and was adopted into the rest of the line up as it contained a host of revisions over what it replaced starting with the turbocharger. The original motor N54 had two turbochargers, one for each bank of three cylinders, but for emissions, weight, and production simplicity it now only has one utilizing what BMW terms TwinPower. The single turbo now has a special exhaust manifold called the Cylinder-bank Comprehensive Manifold (CCM) that feeds both paired cylinder banks into a divided turbocharger housing for a twin scroll effect to boost response.
BMW called on their expertise in the naturally aspirated realm to add their own variable valve timing system, Valvetronic, to the car and tuned it to operate with turbocharged power in mind. At 3-litres of displacement, the BMW 135 6-Cyl. Twin Turbo Engine might sound thirsty, but BMWâ€™s Direct Fuel Injection technology makes sure that all the bases are covered. In the end, the engine makes 306bhp at 5800rpm, provides a stump pulling 295lb/ft of torque from 1200rpm to 5000rpm. The 0-60 sprint can be accomplished in 5.1 seconds while returning an easy fuel mileage peak of 28mpg.