Hybrid, you’ve gotten a bad rap. All along we’ve heard how hybrids may be slow, but the fuel savings make it worthwhile. But we didn’t stop to think that when it comes to performance, if one power source is good, two can be even better. And we didn’t stop to think that a hybrid from BMW would be a high-performance hybrid.
Then enter the 2013 BMW ActiveHybrid 3.
ActiveHybrid? Active indeed. Here’s what make it work. The hybrid arrangement for the ActiveHybrid 3 is a combination of BMW’s TwinPower Turbo 3.0-liter inline six-cylinder and an eight-speed Steptronic automatic transmission with integral electric motor drawing power from a high voltage battery.
But unlike the typical hybrid, the TwinPower Turbo 3.0-liter doesn’t cut power. It’s identical to the 3.0 turbo used in the BMW 335i, rated at 300 horsepower at 5800 rpm and peak—or plateau—torque of 300 lb-ft between 1200 and 5000 rpm. The engine, a multiple award winner, is a technological marvel in its own right, with a twin-scroll (dual nozzle) turbocharger, direct injection and fully variable valve timing.
To that, BMW adds a synchronous electric motor with a maximum output of 55 horsepower but also 155 lb-ft of torque from a standing start. Together the inline 6 and electric motor combine for 335 horsepower and 332 lb-ft of torque, an increase of 13 percent and 11 percent respectively. And that, by any estimation, is a boost in power.
The electric motor is integrated into a new eight-speed automatic transmission that’s connected to the engine via a clutch rather than the conventional torque converter. The eight ratios, of course, allow a wider range of power delivery, from lower, for quicker (and more efficient) off-the line performance, and a higher top gear, allowing for more fuel-efficient low rpm operation at highway speeds.
The electronically-controlled transmission also has direct downshift capability, skipping intermediate gears when shifting automatically to lower gears for shorter shift times for sportier driving. Speaking of sport, an optional sport transmission with even quicker shifting ability is available, though was not on our test 2013 BMW ActiveHybrid 3 model.
Overall efficiency of the transmission is aided by warming and cooling by the internal combustion engine’s cooling system.
BMW hides the lithium-ion high-voltage battery for the ActiveHybrid 3 under the trunk’s floor, inside a special high-strength housing positioned between the rear wheel arches for maximum safety in a collision. Placing the weight towards the rear also helps weight balance.
For the tech minded, the 675 Wh battery is comprised of 96 cells, with battery temperature regulated by the car’s air conditioning cooling system. The hybrid power electrical system runs at 317 volts, running not only the electric propulsion system but the air conditioner compressor as well. The A/C unit doesn’t create a drag on gasoline engine performance but also allows the climate control system to operate even with the engine is not running.
Which we found was more frequently than we expected. Unlike certain hybrid systems’ monitor displays, the ActiveHybrid 3 keeps the tachometer from the conventional non-hybrid 335i, and when the engine is not running, the tachometer drops to “ready.”