From Cadillac Press: The XLR roadster, Cadillac’s bold entry into the elite club of the finest luxury roadsters, enters 2009 with a revised model lineup that is focused on more dramatic design, technology and craftsmanship.
The ultimate convenience of a retractable hard top is a hallmark of the XLR’s design. By pushing and holding a single button, the XLR can convert from coupe to open roadster in less than 30 seconds. The top is made of aluminum and magnesium with composite exterior panels, a heated glass backlight and glass rear-quarter windows.
Two versions of Cadillac’s renowned Northstar engine family power the XLR lineup: a 4.6L V-8 VVT in the XLR Platinum and a 4.4L supercharged V-8 in the XLR-V. (See “XLR-V details” section below for information on the 4.4L supercharged engine.)
The XLR Platinum’s 4.6L engine is a 90-degree, DOHC, four-valves-per-cylinder engine rated at 320 horsepower (239 kW)* and 310 lb.-ft. (420 Nm)* of torque. It offers smooth, quiet and refined performance throughout its entire operating range, yet it is tuned to give the driver feedback from the environment. The 4.6L engine features an aluminum block and cylinder heads, and a valvetrain configuration with roller finger followers.
Both the 4.6L V-8 and the supercharged 4.4L engines are mated to a Hydra-Matic 6L80 six-speed automatic transmission. With a wide, overall ratio of 6.04:1, the six-speed delivers an excellent combination of performance and fuel efficiency. The final drive ratio is 2.56:1.
An advantage of Cadillac’s roadster not shared by competitors is its rear-mounted transmission. This helps give the XLR a virtual 50/50 front-to-rear weight distribution for superior balance, as well as providing occupants with unusually roomy footwell space.