PSA XUD engine

The XUD is an indirect injection diesel engine designed and built by PSA for Peugeot and Citroën, using a version of the Ricardo Comet V prechamber cylinder head. It came in 1.8, 1.9 and 2.1 litre sizes, each naturally aspirated or turbocharged, with single overhead camshaft heads of eight or twelve valves, and it was normally mounted across the front of front wheel drive cars, tilted by 30 degrees. It is built at the Citroën plant at Trémery near Metz. When released it was regarded as one of the best car and light van diesels in the world, and a ready to run XUD9 weighed 157 kg, about 15 percent less than a comparable earlier diesel. PSA licensed a version to Hyundai for the European Lantra, and the engine was the predecessor of the HDi range.