its 20 nm, then 180degrees, then a further 180degrees
run all the head bolts in by hand first, then torque in the following order
10 6 2 3 7
09 5 1 4 8
then go round again with the 20 nm torque, keep going round till they no longer move when torqued, you will find the first ones you did will move a bit
then if you dont have a torque angle gauge mark the head bolt with a pen with a start point, then do the same sequence with the 180degrees turns, at the end all the marks should line up with the original mark
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