This 7 piece set contains essential engine service tools for use with bmw n43 16 amp 20 litre petrol engines compatible with a wide range of engine codes this set ensures that the engine timing is set correctly using the specialist tools engine timing must be set correctly to ensure an engine runs properly if timing is set incorrectly the effects on an engine could be terminal making this set an absolute must have when working on bmw n43 enginesset contains 2 x tensioner locking