The term 'performance enhancer' can be summarized as a tuneup, which is a six-letter word. A tuneup is a process of improving the performance of a vehicle or other machine by adjusting, cleaning, and replacing parts. It is often done to improve fuel efficiency, reduce emissions, and increase the lifespan of the machine. Additionally, tuneups can also help to improve the overall performance of the machine, such as increasing its speed or power.