Thanks Alex, haven't tried a de-rate departure as yet and may be the key as you say. Other issues l've found is the FMC calculated climb and descent speeds - way over the top so having to adjust those (i'm using 280/.78 as my default). Also getting a massive overspeed during the descent (around FL200) when using VNAV. I'll try the next one using FLCH.
Thanks for the help.

Cheers Steve

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