Thanks frog. I'm on a 200 block so it's the 4x4 procedure I "followed". Like you, I now read to it mean 180 degrees then check for 110Nm. All 10 bolts went round to approx 120 degrees when they hit 110Nm

I know that they were all done in the correct sequence and the block was machined flat before I started. The head was fine before it came off - it was a piston problem that lead to the rebuild, not a hg failure.

So I guess I have nothing to lose by adding another 60degrees to each bolt and monitoring the situation for now. I'm running in anyway so won't be thrashing it.