Volvo Cars this week announced that its performance division has created a package to boost the power and performance of the XC90 T8 Twin Engine plug-in hybrid midsize premium SUV. Optimization tweaks from the Swedish automaker’s Polestar motorsports unit in Gothenburg, Sweden, make the new XC90 T8 Volvo’s most energetic factory XC90 ever. It will be available in U.S. dealer showrooms in October.

The T8 Twin Engine hybrid drivetrain, which relies on a 2.0-liter 4-cylinder supercharged and turbocharged engine with an electric motor, has been enhanced in five ways, including improved throttle response; better gearshift hold; refined speed and precision; and extra power for the engine. Optimization means that engine performance has been increased to 421 horsepower from 400 horsepower and torque has been upped to 501 lb.-ft. from 472 lb.-ft. of torque.

Polestar’s latest-generation fine-tuning or optimization not only adds power but also features a gear hold function that holds lower gears during cornering at high g-forces for better handling and balance. In addition, the 2017 XC90 T8 can zip from 0-60 mph in 5.5 seconds instead of 5.6 seconds, according to Volvo. It’s also noteworthy that these Polestar tuning enhancements do not affect fuel consumption, emissions, or the vehicle’s warranty, Volvo says. The hybrid plug-in XC90 is EPA-rated at 53 MPGe.