The Cadillac XLR car is a retractable hardtop marketed by the Cadillac division of General Motors, met in Bowling Green, Kentucky. It is based on the Y-body platform shared with the Chevrolet Corvette. The Cadillac XLR uses the Northstar engine rather than the GM LS2 engine found in the Corvette - with its own style, interior and suspension, and power-retractable rigid aluminum. The Cadillac Northstar engine is tuned for 4.6 L 320 hp (238.6 kW/324.4 PS), Associate model year 2007 at a speed automatic transmission 6.