The XK engine is a six-cylinder engine developed by Jaguar in the late 1940s. It features a dual overhead camshaft design and is known for its smooth performance and high power output. The engine was initially used in the Jaguar XK120, a sports car that gained popularity for its speed and elegance. Over the years, the XK engine has been adapted for various models, including the Jaguar E-Type and Jaguar Mark 2. Its robust design and engineering excellence have made it a significant part of Jaguar's legacy, contributing to the brand's reputation for luxury and performance.