More stories related to 2005 NAIAS DETROIT – General Motors Corp.’s Cadillac Div. will expand its V-Series performance lineup to its well-received STS sedan this year, the auto maker reveals here at the 2005 North American International Auto Show.

The ’06 STS-V, expected to arrive during the fourth quarter, will deliver the highest horsepower rating of any production Cadillac engine in history – a throttling 440 hp – and is the first GM vehicle to use the company’s new 6-speed automatic transmission.

Joining the CTS-V among the enthusiast-aimed vehicles offered by the luxury division, the STS-V is powered by a new 4.4L version of the 4.6L Northstar DOHC V-8 outfitted with an intercooled supercharger and variable valve timing.

’06 Cadillac STS-V

Called the Northstar V-8 SC (supercharged), the engine’s power is underscored by its ability to deliver 90% of its peak torque between 2,200 and 6,000 rpm. Vehicle redline is 6,700 rpm. The Northstar V-8 SC generates 120 hp more than its naturally aspirated counterpart, while its 100 hp/liter makes it one of the world’s highest specific output production V-8 engines, says Tom Stephens, group vice president-GM Powertrain. A 0-60 mph (97 km/h) time of less than 5 seconds is expected for the STS-V.

Notably, Cadillac’s use of a supercharger occurs as rival Mercedes-Benz plans to abandon forced-induction engines for larger-displacement, naturally aspirated mills in its future AMG performance models.

Meanwhile, the 6L80 6-speed automatic transmission – launching in the STS-V – incorporates Performance Algorithm Shifting (PAS) and Driver Shift Control (DSC). PAS lets the electronic transmission controller override the automatic gear selection during closed-throttle high-lateral acceleration maneuvers, rapidly downshifting with the release of the torque converter clutch for smooth powering up when the throttle is reopened. DSC allows the driver to sequentially changes gears manually via the gearshift lever.

Tested at GM’s all-new Milford (MI) Road Course facility and the famous Nurburgring race track in Germany, STS-V is equipped with 18-in. front wheels and 19-in. rear wheels, increased brake-rotor diameters, larger pad areas and larger calipers, stiffer stabilizer bars and suspension springs and a faster steering ratio.

Exterior styling includes the V-Series’ signature stainless steel wire mesh front grille, and lower front and rear fascias and rocker panels. The car looks as wicked as a caged shark.

The hood’s center is raised to provide space for the engine’s supercharger. The tail spoiler is positioned higher and more rearward.

The STS-V’s interior is dark but luxurious, featuring extensive leather surfaces, ash burl wood appointments, aluminum accents and suede seat inserts.

GM’s Lansing (MI) Grand River plant will build the STS-V.