There are several synonyms for the phrase "increase car agility". Firstly, the word "nimbleness" could be used to describe the ability of a car to move with quick and precise movements. Another synonym is "dexterity", which refers to the car's ability to handle sharp turns and curves with ease. "Maneuverability" also describes a car's ability to navigate through cramped spaces or tight corners. Additionally, "responsiveness" is a term that can be used to describe a car's ability to quickly react to the driver's commands. Overall, there are many ways to describe the notion of increased car agility, and these synonyms can be useful in conveying the idea to others.