Volvo is in the process of transforming its in-house tuner Polestar into a standalone brand for high-performance electrified cars.

The standalone Polestar is expected to make its splash on the world stage with a concept at next month’s 2017 Frankfurt auto show.

The company is still going to tune Volvos, though. The latest are the 2018 S60 and V60 Polestar high-performance sedan and wagon.

The cars were just given a heart transplant in the form of a 2.0-liter turbocharged and supercharged inline-4 for 2017. For 2018, they receive carbon fiber aero upgrades claimed to boost downforce by 30 percent. This in turn is said to improve grip and high-speed stability.

2018 Volvo S60 Polestar

2018 Volvo S60 Polestar

Using experience gained from the Cyan Racing, which races a dedicated S60 racecar in the World Touring Car Championship, Polestar engineers designed a new front splitter, side sills and a rear spoiler extension, all made in carbon fiber.

Other changes for 2018 include a black gloss finish for the 20-inch wheels, plus carbon fiber side mirror caps and the new exterior color Bursting Blue Metallic. The interior has been updated with a new seat lining, blue contrast stitching and Polestar embroidering.

Peak output from the 2.0-liter engine remains capped at 362 horsepower and 347 pound-feet of torque. This is channeled to all four wheels via an 8-speed automatic. Polestar quotes a 0-62 mph time of 4.7 seconds for the S60, and 4.8 seconds for the V60. Top speed is governed to 155 mph on both.

Just 1,500 S60 and V60 Polestar models will be built for 2018, with each receiving a unique number on the tread plate. Availability in the United States is yet to be announced.