The 2007 XLR is a 2-door, 2-passenger convertible sports car, available in one trim only, the Convertible.Upon introduction, the XLR is equipped with a standard 4.6-liter, V8, 320-horsepower engine that achieves 17-mpg in the city and 27-mpg on the highway. A 6-speed automatic transmission with overdrive is standard.