Range Rover retrieves its HST trim from the fine china cabinet when it wants to introduce something special. Three years ago, the aristocratic English carmaker debuted a Range Rover Sport HST at the New York Auto Showwith the first use of its 375-horsepower supercharged V6. This year, a brand new Range Rover Sport HST debuts Land Rover's Ingenium 3.0-liter inline six-cylinder, and its first production mild hybrid. The motor produces 394 horses and 406 pound-feet of torque.

A straight-six has been rumored for Jaguar Land Rover for at least four years, once predicted to hit the market at the end of 2016. Now that it's here, we find its output comes courtesy of an electric supercharger and a turbocharger. Power numbers slot just above the 375-hp HSE Dynamic that uses the 3.0-liter supercharged V6, an engine we'll assume is headed for the exit. For the moment, the new straight-six will only be available on the special edition HST.

The supercharger can spool up to 120,000 rpm in half a second, which Land Rover says eliminates turbo lag. On top of that, the carmaker's first 48-volt mild hybrid system uses brake energy recuperation to charge a set of batteries that powers an electric motor. Land Rover didn't provide specs on the e-motor. The energy can be deployed during hard acceleration, helping scoot the Range Rover Sport from 0 to 60 in 5.9 seconds and on to a top speed of 140 miles per hour.

The HST trim offers five colors and two wheel designs, with brake calipers in either red or anodized gray. The 16-way front seats wear a new color pattern, and suede cloth covers the steering wheel and shifter. HST badges appear throughout.

Land Rover hasn't announced U.S. pricing yet. In the UK, the Range Rover Sport HST is priced a few thousand pounds under the Autobiography Dynamic trim. If that holds true for us, expect an MSRP just over $90,000. If not before the show, we can expect to get all the details in April in New York.