• 443-horsepower Supercharged Northstar V-8 Engine
• Rear-Mounted Hydra-Matic Six-Speed Automatic Transmission
• Handcrafted Leather-wrapped Interior
• Adaptive Forward Lighting System
• V-Series Design Cues Throughout

The 2006 Cadillac XLR-V – the newest addition to the luxury nameplate’s growing family of high-performance V-Series vehicles – takes the performance and luxury of Cadillac’s acclaimed luxury roadster to its fullest extent.

The 443-hp XLR-V arrives in early 2006 as Cadillac’s quickest, most agile and most exclusive production vehicle. Built in very limited quantities, the XLR-V blends advanced performance technology with an added element of hand-crafted luxury.

Like its mainstream XLR sibling, the XLR-V combines distinctively bold styling with contemporary luxury, ingenious technologies, rear-wheel drive performance, and near 50/50 weight distribution for enhanced balance and vehicle dynamics – yet it does so on an entirely different level:

• Equipped with a supercharged Northstar engine and rear-mounted six-speed automatic transmission, the high-performance luxury roadster effectively delivers 0-to-60 performance in 4.6 seconds;

• Exterior and interior appointments express both elegance and aggressiveness. These details also clearly communicate V-Series family traits, including application of a signature wire-mesh grille, larger 19-inch wheels at all four corners, and ebony wood and aluminum accents throughout the interior;

• Chassis refinements that create the most agile production Cadillac ever, on the street or the track. These include larger brakes, stabilizer bars, wheels and tires, and a performance-calibrated Magnetic Ride Control (MR) system;

• An Adaptive Forward Lighting system, a first-time application on a Cadillac, which automatically adjusts headlamp direction up to 15-degrees for improved night driving vision.
The XLR-V represents a 21st century version of Cadillac’s hand-crafted coach building heritage. Like XLR, the XLR-V is built at GM’s state-of-the-art, award-winning Bowling Green assembly center, an operation using both advanced technology and hand-craftsmanship. XLR-V’s interior features hand-wrapped and hand-stitched leather and exotic Zingana wood. Each supercharged Northstar engine is built by a single craftsman from start-to-finish at GM’s Performance Build Center in Wixom, Mich.

Supercharged Northstar engine

At the heart of the XLR-V is the new, 4.4-liter version of the Northstar engine outfitted with a positive displacement intercooled supercharger. The dual overhead cam (DOHC) V-8 engine delivers the highest horsepower rating of any Cadillac engine to date.

Called the Northstar V-8 SC (supercharged), the engine produces 443 horsepower (328 kW) at 6400 rpm and 425 lb.-ft. (576 Nm) torque at 3600 rpm (power and torque figures estimated) – and the engine’s power is underscored by its ability to deliver 90 percent of its peak torque between 2200 and 6000 rpm.

The Northstar V-8 SC generates 123 horsepower (90 kW) and 115 lb.-ft. (156 Nm) of torque more than its naturally aspirated counterpart, while its specific output of more than 100-horsepower-per-liter makes it one of the world’s highest specific output production V-8 engines.

However, the Northstar V-8 SC used in the XLR-V is more than just power and torque. The DOHC engine includes variable valve timing that enables outstanding top-end performance while maintaining the expected refinement and quality associated with a luxury marque.

The aggressive torque curve enabled by the choice of a supercharged engine gives the XLR-V acceleration capable of placing it firmly in the under-5-second-club for 0-to-60 time – a signature capability of V-Series vehicles.
The refined shift feel is enabled by careful electronic calibration of both the engine and transmission. During shifts, power is instantaneously lowered, then ramped back up carefully to make gear changes virtually unnoticeable.

Air induction & exhaust

The air induction system on the XLR-V was redesigned to address packaging needs created by the larger engine and addition of the supercharger.

These modifications increased the flow of air to the engine by 30 percent, funneling it from the front air intake over the radiator and to the supercharger via two ducts, which converge into one prior to reaching the supercharger so only one mass air flow sensor is required.

The system was designed to be as free flowing as possible, bringing in the maximum amount of air to the supercharger. Each duct has been carefully tuned to minimize supercharger whine and resonance in order to achieve the most pleasing intake sound quality.

XLR-V is a dual personality car, both a refined luxury cruiser and a serious performance machine. The car’s exhaust system literally changes to suit both personalities. The exhaust system features a unique muffler design, which effectively combines the construction of a more conventional muffler with a high-performance flow-through design. In order to keep sound levels at a pleasant, throaty pitch during everyday driving on streets and expressways, the exhaust is routed through a series of internal chambers that muffle sound levels. During more aggressive driving, a vacuum-actuated Pierburg valve in the muffler opens to allow straight exhaust flow-through. There are some perforations in the pipe to allow some dissipation into the other muffler chambers, but the overall effect is to reduce backpressure and increase power.

Six-speed automatic transmission

The Northstar V-8 SC is mated to the all-new Hydra-Matic 6L80 six-speed automatic transmission – the first use of General Motors’ new six-speed automatic in a rear-mounted configuration.

The 6L80 – the only transmission offered on the XLR-V – is one of the most technologically advanced automatic transmissions in the industry, using clutch-to-clutch operation and an advanced integrated 32-bit transmission controller to deliver smooth and precise shifts. In addition, a wide 6.04:1 overall ratio spread enhances performance and fuel economy.
The 6L80 also incorporates advanced driving enhancement features, including advanced 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. Driver Shift Control allows the driver to sequentially shift gears manually via the gearshift lever.

Performance-tuned chassis systems

With GM’s patented Performance Car architecture as its basis, the XLR features a lightweight construction, nearly optimal weight distribution and sophisticated chassis providing both luxurious ride and outstanding handling characteristics. With XLR-V, the bar has been raised. The chassis is finely tuned to enable the dual character of the car, with enhancements providing very serious performance without compromising its smooth and refined road manners.
Chassis modifications found on the XLR-V when compared to its mainstream sibling include larger brakes; recalibrated Magnetic Ride Control (MR); larger front stabilizer bar and the addition of a rear stabilizer bar; stiffer rear lower control arm bushings; larger wheels and tires; a power steering fluid cooler; and a higher-capacity fuel pump.

In concert with the car’s great power and handling capabilities, XLR-V’s braking system has been bolstered, assuring strong stopping power and smooth, confident brake operation.
To achieve this, chassis engineers turned to J55 brakes, essentially the same application used in the Z51 performance package of the Chevrolet Corvette with larger cross-drilled rotors and high-performance brake lining. Front rotors are 13.4-inches (340.4 mm) in diameter; rear rotors are 13.0-inches (330.2 mm). The thickness of the rotor cheeks on both the front and rear has been increased for added thermal capacity. The brake system incorporates dual-piston front calipers, and single-piston rear calipers.

Magnetic Ride Control on the XLR-V has been recalibrated to account for the enhanced handling characteristics the roadster’s surpercharged performance demands. The system seeks to keep the body on an even plane at all times, giving drivers a comfortable ride by dramatically reducing disturbances to the vehicle body.

The MR recalibration – combined with a stiffer front stabilizer bar, the addition of a rear stabilizer bar, and stiffer rear control arm bushings – subtly changes the driving characteristics of the XLR-V when compared to the standard XLR. Additionally, when the driver moves the shifter into the manual mode – indicating more aggressive operation -- the MR settings adjust to a “sport” mode that is more track-ready than the default “touring” setting. Another V-Series staple is a four channel/four-selection mode chassis control system (StabiliTrak), enabling the driver to switch between four stability settings, including a "less-governed" performance mode for the performance enthusiast.

Wheels and tires have been increased in size for enhanced sure-footedness, to 235/45R-19 on the front and 255/40R-19 rear. The tires are Pirelli run flats.

Cooling strategies for high performance

To meet the increased demands of the XLR-V powertrain and power steering systems, a number of enhancements were made in the cooling systems to assure the vehicle can realize its full performance potential while meeting all the expectations for refinement and sophistication in an ultra-luxury roadster. These enhancements include:

• Auxiliary engine oil cooler (EOC);

• Auxiliary transmission oil cooler (TOC);

• Large auxiliary cooler inlet and outlet openings;

• Dedicated supercharger radiator;

• Power steering fluid cooler, which consists of a tube wrapped with wire bristles, giving it an appearance similar to a hairbrush. Unlike more traditional finned coolers, the bristle design allows air to flow through the cooler from all directions, creating more efficient and effective cooling;

• Louvers have been added in the wheel liners behind the auxiliary coolers to exit air from the coolers and to help improve brake cooling.

V-Series styling modifications

Styling modifications have imparted a more aggressive character to the XLR-V in keeping with its enhanced performance capabilities, while retaining an aura of refined elegance.

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