An alpine Mini Paceman, yodeling in the key of ‘D’

There are three ways to climb from the floor of the Adige Valley to the Mendel Pass, a 1,363m notch in the Mendelkamm – a 35km mountain ridge that forms a border between the northeastern Italian province of Trentino and the autonomous region of Südtirol/Alto Adige.

Intrepid souls can make the ascent via a number of immaculately maintained hiking trails. From the village of Kaltern, one can ride the Mendelbahn, one of Europe's longest and steepest funicular railways. Lastly, driving north on the Weinstrasse/Strada del Vino, a motorist can make a sharp left just before the village of St Michael and head up the SS42, a road as beguiling for its concentration of hairpin turns as it is unnerving for the swarms of motorcyclists that race up and down its length at breakneck speeds.

On a cool and overcast afternoon, on a particularly nasty curve, a Ducati lay on its side smack in the middle of the pavement. Standing on the road's shoulder, a rider whose scuffed leathers suggested he was the downed Ducati's pilot mimed his wipeout to his companions as they stood around him in a semicircle, looking on with a kind of rapt apprehension.

There was plenty here to make a driver apprehensive. Roadside mime shows are precisely the sorts of things that cause drivers so distracted to pitch off into the Adige Valley's airy void. Best to focus on the road ahead – and the inspiration for this jaunt, a 2013 Mini Cooper SD All4 Paceman.

What made this particular Paceman special, especially for a driver from the US, was its power plant, a 2-litre four-cylinder turbodiesel, denoted by the “D” in its SD designation. According to Dr Kay Segler, Mini's senior vice president of business coordination and brand management, a full 40% of the Minis sold in Europe are diesel-powered. By contrast, precisely 0% of Minis sold in the US run on the stuff – because there are none to sell.

Given diesel's advantages over gasoline, this is lamentable. Though they traditionally cost more and emit slightly higher levels of particulate matter, diesel engines deliver both excellent fuel economy and tremendous low-end torque – the force that gives a car its oomph. The all-wheel-drive SD Paceman's 2-liter engine produces 225lb-ft of torque between 1,750-2,700rpm. By comparison, the highest-performance gasoline-powered Paceman – the John Cooper Works – produces 206lb-ft. That oomph factor does not dilute fuel economy, however, with the SD trouncing even the least powerful petrol-burning Paceman.

Having all that torque at relatively low revs has a way of changing a driver’s behaviour. Slaloming up a road such as the SS42, the temptation to upshift as early as possible – all in the service of staying in that magic place where torque flows like rivers and the slow-turning engine's low drone harmonises with the turbocharger's nearly ultrasonic whine – is irresistible.

Between the hairpins, the SD's acceleration was fluid, effortless, yet of a very different stripe than that of gas-burning Minis. Pin the accelerator on a Cooper S, and the needle races to redline. Push the SD much above 3,000rpm, and the torque curve flattens while the engine grinds out a dirge of protest. This behaviour is inherent to diesel engines, which have significantly higher compression ratios, longer piston rods and correspondingly longer crank-pin offsets, which together conspire to generate more torque than a comparably sized gasoline engine. The flipside, though, is that the heavier, more robust components limit engine speed.

The more a diesel arriviste revels in the SD’s low-rev torque, the more the idea of revving an engine to its limits begins to feel quaint and somewhat gratuitous. In spite of its relaxed engine dynamics, the Paceman was unquestionably sporty, quite the opposite of the lumbering slowpokes many Americans imagine when they hear the “D” word.

In the US, there is a contingent of drivers which salivates at the win-win prospect of diesel-powered Minis. BMW Group, Mini’s corporate parent, is aware of this, and as early as 2007, was planning to bring a diesel Cooper to the US in 2010. Those plans, however, were scuttled by the global financial crisis, and by the costs and technical challenges of equipping the car with an anti-smog urea injection system to comply with changes to federal emissions regulations that would take effect in 2013.

In an email exchange, Segler wrote that Mini is still considering the prospect of diesels in the US, although he qualified the statement carefully.

“It is not entirely clear if our owners are asking for a 47mpg gasoline car or a diesel-powered car,” he wrote. “What is clear is that our owners want highly efficient cars. We will have highly efficient gasoline engines and are looking at the option of including diesel as well.”

After a long, twisty descent from the pass’s apex, downshifting this time for a bit of engine braking, it was back on the Weinstrasse/Via del Vino. This seemed a perfect moment for reflection, to take in the verdant Gewürztraminer Plateau. But on cresting a small hill, the Paceman came grille to grille with a tractor driven by a farmer engaged in an important phone call. For a moment, sheer terror mingled with feelings of kinship towards a man who no doubt had a much deeper appreciation of diesel-engine physics than this American driver would ever have. The Paceman swerved right, the tractor swerved left. With oblivion avoided by mere centimetres, the two machines clattered merrily along, in their own way.

Vital stats: 2013 Mini Cooper All4 SD Paceman

  • Base price (UK): £24,290 (inclusive of £4,048.33 20% VAT)
  • Price as tested (UK): £26,780
  • Fuel economy (EU cycle): 8.4 l/km city, 6 l/km highway
  • Powertrain: 2-litre 143hp turbocharged four-cylinder diesel engine, six-speed automatic transmission, all-wheel drive
  • Standard features: rear spoiler, three-spoke leather-wrapped steering wheel, Mini Connected telematics system, performance suspension, Dynamic Traction Control, adaptive Xenon headlamps, seven air bags
  • Major options: navigation, automatic transmission, fog lamps, rain sensor, automatic climate control, lighting package