CSF Racing Oil CoolerBMW S54 Swap E36 Race Spec Dual Pass Oil Cooler Any who has ever tracked an E46 M3 or even just driven one hard knows how quickly the oil temperatures can climb. For the E46 M3, CSF developed the Dual Pass Race Spec Oil Cooler (CSF #8032) with Rogue Engineering. This has been the go to solution for the E46 M3 community and will work on S54 Swaps when paired with this radiator. Why are there two oil coolers then you might ask? Because of the chassis