The Alfa Romeo Boxer engine was a water-cooled flat-4 piston engine developed by Alfa Romeo for front-wheel drive, longitudinal applications.It debuted on the Alfasud, which was introduced in 1971 at the Turin Motor Show. In the following decades the Boxer went through several upgrades and powered all Alfa Romeo front-wheel drive cars up to 1996. In 1997 it was phased out and replaced by the transverse-mounted Twin Spark engines.