Royal Purple Royal Purple combines premium synthetic base oils with proprietary additive technologies to exceed protection and performance requirements of new modern engines. These often include smaller displacements, turbo chargers, gasoline direct injection (GDI), and start/stop systems. Modern gasoline direct injection (GDI) engines have achieved levels of power and fuel economy never before possible in passenger car engines. As a result, smaller engines operate at much higher loads across all engine speeds. This has caused increased wear in critical areas of the engine, and created a destructive phenomenon called low-speed pre-ignition (LSPI). The unique, state-of-the-art additive technology in Royal Purple High Performance engine oils is designed specifically to address these issues, and help engines maintain performance and reliability.