The APR Air-to-Water Intercooler System for the B9 RS4 / RS5 2.9T EA839 offers a substantial leap in performance that directly translates to more horsepower and torque, and consistent performance that's unmatched by the factory cooler. The factory cooler struggles to cool the charged air resulting in excessive intake air temperature due to its small size. This struggle results in ECU protecting the engine by pulling power during a single quarter mile pass, lap around a track, or even during a spirited drive. Simply bolting on the APR System relieves this issue, resulting in an instant boost in power and consistency. The APR system has no trouble remaining consistent thanks to its ability to resist power-robbing heatsoak!