The P4 was based on a design for Studebaker by Raymond Loewy, famous for his streamline shapes. It was announced in the Autumn of 1949. Although the body was completely new, much of the chassis was P3. The P4 75 had the traditional Rover 3-lamp configuration at the front, which earned the car the nickname of Cyclops. The engine was basically the P3 2103 cc six-cylinder in-line unit, but now fitted with an aluminum cylinder head.