The addition of a six-cylinder engine to BMW's flagship 7-series lineup might let the recession's sour taste seep into the mouths of some Bimmer fans, but it shouldn't. After all, the 7-series was a six-cylinder-only model from its U.S. introduction for 1978 until 1988, when the twelve-cylinder 750iL debuted. BMW hasn't built a six-cylinder 7-series for the U.S. since the 1992 model year (the 735i), but the twin-turbo straight six in the 2011 740i and long-wheelbase 740Li is a big-league engine that's clearly worthy of BMW's top sedan, what with its 315 hp and 330 lb-ft of torque. Indeed, the powerplant produces nineteen more horsepower and only two fewer pound-feet than the aforementioned V-12 7-series of twenty years ago.
Most importantly, the new 740 cars are still pretty darn quick. In fact, according to BMW, the twin-turbo six-cylinder models give up only 0.7 second in the sprint to 60 mph compared with twin-turbo V-8 750s of similar wheelbases (5.8 seconds for the 740i versus 5.1 seconds for the 750i). During a test-drive of a 740Li in rural New Jersey, we were particularly impressed by the fact that the six-cylinder car, which is about 220 pounds lighter, exhibits less turbo lag off the line and therefore smoother, more linear acceleration---V-8 variants, which have an 85-hp advantage, hesitate off the line before exploding forward. Like the V-8 version, the 740Li uses a six-speed automatic transmission that provides smooth upshifts and very responsive downshifts as well as a Sport mode. The 740 retains the 7-series' highly impressive sporty-big-car handling characteristics and also comes with so-called Driving Dynamics Control, a rocker switch next to the shifter that allows the driver to choose among four different driving programs---Comfort, Normal, Sport, and Sport Plus---that tweak the calibrations of the dampers, transmission, gas pedal, steering, and traction control.
The new six-cylinder 7-series is powered by an uprated version of BMW's "N54" engine, a direct-injected, twin-turbo straight six that debuted with 300 hp and 300 lb-ft in the 2007 335i coupe. (Incidentally, that engine has already been partially replaced by the "N55" six-cylinder, which provides similar power with a single turbocharger and is found in 2011 editions of the 135i, the 335i, and the 535i, as well as "35i" versions of the Z4 and the X6. In addition to the 740i, the N54 engine also sticks around for the hot new 335is and Z4 sDrive35is models.)
BMW credits its U.S. dealers for inciting the return of six-cylinder power to American-market 7s; in late 2008, many BMW dealers were invited to Europe to drive the fifth-generation 7-series, and they apparently came away very impressed with the Euro-market 740 vehicles. Those dealers finally got the 740i and 740Li in the States in April, when the cars went on sale for a base price of $71,900 and $76,300, respectively, and comprised about ten percent of overall 7-series sales. BMW estimates that the six-cylinder's volume will eventually settle between ten and fifteen percent. (By the way, about 70 percent of 7s sold in the U.S. are currently long-wheelbase models, which carry a $3900 premium over standard-length V-8 cars and a $4400 surcharge for 740s. The twelve-cylinder 760Li's small slice is only about two percent of the entire 7-series pie.)