This is my video on how to change timing on N42B20, N42B18, N46B20 engines. This is super similar to N45 engines so don't be afraid to watch it before you try to change it. I tried my best to show as much as possible and to make video enjoyable to watch. It is not super difficult and I believe you can do it yourself.
Apart from common hand tools you'd need a set of engine locks or blockades to time the engine correctly and a torque wrench. BMW is very easy to work on so don't be afraid and if you have any questions leave them in the comments or reach out on IG ;)
Have a good one!
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