Hi All,
Alph does not say if the head is alloy or iron, in either case check that the head bolts thread down far enough and easily into the barrel
The washers on the head bolts squash and distort even on the iron heads
The faces on the head for the washers also distort
Make sure they are flat or get them spotfaced
I make 3mm thick washers for the bolts
machined from bar stock
Touch wood
I have not had to go back and retighten any of the heads on the engines I put together over the years
John