The current top inline-six motor in non-M cars is a 3.0-liter unit codenamed the M54. The 225 horsepower powerplant
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| With so much riding on the inline-six engine, BMW engineers are constantly under pressure to ensure new versions of the powerplant live up to their predecessors. (Photo: BMW Canada) |
with 214 lb-ft of torque (231 and 221 respectively in Europe) features Double-Vanos (BMW's version of variable valve timing), which helps to increase overall output while reducing consumption and emissions from its 2.8 liter 'M52' predecessor. The awards and accolades that the M54 has picked up are enough to crown it a heavyweight, but for the fact it weighs just 171 kg (377 lbs) it's one of the world's lightest six-cylinder engines.
Powering the 330, 530, X3 3.0, X5 3.0 and Z4 3.0, the engine's flexibility is clearly demonstrated in the variety of its applications. BMW's reputation for creating engines that are powerful, yet refined and economical puts great pressure on the engineers in charge of designing a replacement. Their research and development has paid off, or so it seems on paper at least.
Enter the R6, which will one-up the M54 at least as authoritatively as the current engine improved on the M52. Rather than calling the R6 a completely new design, BMW refers to it as a redesign. The object was to make it stronger, lighter and more powerful. Addressing the demand for more power, important being that the current M54 lacks punch when
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| Stronger, lighter and more powerful, it looks like BMW has hit the mark with the new R6 engine. (Photo: BMW Canada) |
stacked up against new competitors from Acura and Infiniti, plus Mercedes-Benz' new 3.5-liter V6, the most significant modification is the adaptation of Valvetronic to the M54's design. Already available in four-, eight-, and twelve-cylinder motors across the engine range, it is only logical that its application in a six-cylinder would be next. Valvetronic removes the butterfly valves which control the throttle, replacing them with an electronic motor, gears and rocker arms synchronized to alter valve lift, controlling the amount of air that enters the engine. The addition of Valvetronic has upped the engine's redline by 500 rpm to 7,000, while helping to raise power outputs and flattened the torque curve. The new engine posts an increase of 27 horsepower to a total of 258 maximized at 6,650 rpm, while 221 lb-ft (300 Nm) of torque is accessible between 2,500 and 4,000 rpm, rather than the peak of 3,500 in the M54.
