Volvo vehicles still bear the styling cues, the emphasis on safety and occasional quirks that endeared the brand to many American drivers during the 1960s through 1990s. But evidence of a transformation across the range of Volvo product lines is unmistakable. Emblematic of that new vision is the S60 T6 Polestar, a high-performing version of the successful midsize 4-door sedan Volvo has been selling since 2001.

What’s a Polestar? Look for the postage-stamp-sized blue square here and there on the body and inside this special S60. It indicates this car has been re-engineered by Volvo’s racing partner, Polestar, in Gothenburg, Sweden, to be remarkably fast, balanced and lithe. Yet it has the same 5-star safety rating resulting from government crash tests of the standard S60, and has been rated a Top Safety Pick Plus by the Insurance Institute for Highway Safety.

Don’t waste your life prowling the parking lots of America in search of a Polestar Volvo. They’re a little less rare than 1948 Tucker Torpedoes, but not much. Just 274 Polestar S60s and V60s will slip into U.S. ports this year, a little more than double the number of 2014 models that made landfall in the United States. We had the good fortune to spend a week with one, rendered in Polestar’s signature Rebel Blue color – curiously similar to a shade of blue commonly seen years ago on 240 sedans and wagons, but more electric.

Functionally, the Polestar S60 does everything the popular S60 does. It swallows 12 cubic feet of luggage, seats four comfortably and five in a pinch (as long as the back-seat passengers are fairly small), and it delivers good but not great fuel economy – 18 mpg city, 27 highway. There, the similarity ends.

Under the Polestar S60’s hood lurks a turbocharged inline 6-cylinder engine that’s rated at 345 horsepower. Under the 20-inch alloy wheels can be found Polestar/Brembo brake calipers. There’s even more magic in the suspension and drive system: Polestar-calibrated all-wheel drive with instant traction; corner traction control through torque vectoring; carbon fiber reinforced front strut brace; Ohlins DFV shock-absorber system. Polestar, which works exclusively on Volvo cars, is quite serious about turning the relatively mild-mannered S60 into a screaming speedster.

Compared with the conventional S60, the Polestar version is just as quiet and composed on smooth roads, aside from a well-tuned exhaust note. But its suspension is much stiffer – buckboard-stiff on bridges with winter-ravaged road surfaces.

Given the attention to performance detail Polestar devotes to each of the few Volvos it sends out into the world, the price is on the high side. Our S60 had a base price of $60,225. But the price is a bit less shocking when you consider the Polestar Volvo comes with a long list of standard features that are optional on garden-variety S60s. (The base price of an S60, with a turbocharged, 240-horsepower inline Five, is $33,950.)

Steven Macoy ( is a longtime car enthusiast and full-time editor who lives in Bethel, Conn.

Price: $60,225

Engine: 3-liter twin-scroll turbocharged inline 6, 345 horsepower, 369 lb.-ft. torque

Transmission: shiftable 6-speed automatic

Drive: all-wheel

Performance: 0-60 mph, 4.7 sec.

Weight: 3,684 lb.

Suspension: MacPherson strut front, multi-link rear

Wheels: 20x8 Polestar bespoke

Tires: 245/35 ZR20 (95Y) XL

Seating capacity: 5

Luggage capacity: 12 cu. ft.

Fuel capacity: 17.8 gal.

Fuel economy: 18 mpg city, 27 mpg highway

Fuel type: premium unleaded gasoline