CSF F8x M3/M4/M2C Auxiliary Radiators w/ Rock Guards (Fit Left & Right)Like the other cooling systems on the F8X, the factory auxiliary radiators do a pretty good job in stock form. However, once you start adding a lot of power and pushing the car in aggressive driving conditions, the factory systems start to show its limitations. As more and more owners have pushed the limits of their S55, CSF saw the need and demand. The F8X platform is also almost a decade old with the newest examples being at least 5 years old. Over