The Rolls-Royce Ghost that Tom recently drove at Road America in Wisconsin.

With a sticker price of $356,290 nicely equipped, the Rolls-Royce Ghost ought to be refined. And after just a few short miles behind the wheel, I was impressed by the car’s overall silkiness. But, while the ride is smooth to the point of mimicking large watercraft, it is the drivetrain polish that really got my attention.

Power, best described as ample, is delivered in a manner so subtle as to somewhat blunt the sensation of gathering speed. And, just as a hypermiler might learn to drive a hybrid vehicle for maximum efficiency, a Ghost driver is in a position to drive the car for maximum seamlessness. This is a challenge I accepted.

Turns out that Rolls, a property of BMW along with Mini, designed the 6.6-liter V12 that powers the Ghost for optimal torque, this in the name of reducing the number of shifts required of the transmission. In the search for torque, Rolls started with BMW’s excellent N74 6.0-liter V12.

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With an “over-square” design—more cylinder bore than stroke—the BMW engine revs freely yet still generates oodles of torque thanks to its generous displacement. For Rolls duty, the engine is enlarged by six-tenths of a liter, with all that extra displacement coming from added stroke. The payoff, of course, is even more torque, and lots of it. The Roller mill produces a healthy 575 pound-feet of torque at just 1500 rpm—really, just off idle.

All this low-end power rewards smoothness-seekers with effortless launches. Additionally and most importantly, the Ghost’s transmission isn’t required to hunt for gears in low-speed driving, thus avoiding the kind of shifting that interrupts tranquil motoring.

I found that I was able to apply just enough throttle to delay shifts while avoiding undue engine revs. While even at full throttle, this big 12 is hardly noisy; in fact, it’s hardly heard.

Worth noting: Our extended-wheelbase (EWB) test car was new to the North American market for 2012. The added length is found entirely in the rear seat area, which now offers stretch-limo quantities of legroom—without the cheap running lights or week-old Wall Street Journal.

The EWB was designed for the Chinese market, where status comes not just from owning a nice car but from having someone else drive you around in your nice car. According to Rolls-Royce, about two-thirds of Ghosts sold in China are extended models. Here in North America, where we’re more likely to drive ourselves around, the take rate on the long version is about 30 percent.

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