Hybrid Racing Performance Radiator Cap

The cooling system of your car is one of the most important parts, without it your engine would be useless in minutes. Many people change the cap for esthetic reasons alone, and while we like things to look good, there has to be a more important reason. Other than the most obvious reason, allowing you to fill your radiator, the radiator cap is an essential part of the system. As the coolant gets hot it expands creating pressure inside of the system, and when it reaches a certain point this pressure is then released through the radiator cap plunger into an overflow tank. Once the pressure has dropped below a desired level the plunger inside of the cap will close.