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There are two basic groups, B38 gasoline units and B37 diesels, and all feature BMW’s TwinPower Turbo technology, which combines a twin-scroll turbocharging system with direct fuel injection, and in the case of the gasoline units variable valve timing as well. One unique aspect is the addition of BMW’s Valvetronic throttle-free load control system, which relies on varying the valve lift to control power rather than a conventional throttle valve.
Billed as the latest initiative of BMW’s EfficientDynamics green technology, the three cylinder engines all displace 1.5 liters and share roughly 60 percent of their components. In fact, this will be the first of BMW’s gasoline and diesel engines that are manufactured together.
The B38 gasoline units develop between 121 and 221 horsepower and 133 and 177 pound-feet of torque, while the B37 diesel units develop between 80 and 181 horsepower and 166 and 243 pound-feet of torque. Fuel economy and CO2 figures will be announced when specific vehicles using the engines are launched.
As for NVH levels, BMW says a torsional vibration damper helps things remain smooth, even at lower revs, while high frequency sounds emitted make the engine seem much sportier than even the four-cylinder units. We’ll have to wait until we drive one to confirm those claims.