MK3 Focus ST/RS Oil Control SystemRemoving the 18lb crankshaft balance shaft assembly from the 2. 0L EcoBoost engine frees up rotating mass and helps to improve engine response. However, removing the balance shaft assembly alone can cause oil starvation issues during high G load corners and extreme driving because of the void left behind in the oil sump and simply installing a balance shaft delete alone can lead to engine damage in certain conditions, due to inadequate engine oil