for future reference:
Stock Head bolts:
78nm then loosen all bolts fully.
Then 20nm + 90­° + 90°
If it is ARP / Cosworth head bolts:
Then with the supplied moly lube used:
I do it in stages of,
20ftlb, 40ftlb, 60ftlb, 80ftlb.
If it's the uprated L19 ARP / Costworth Head bolts:
Again with the supplied moly lube used:
20ftlb, 40ftlb, 65ftlb, 85ftlb.
Note the stock bolts are in Nm and the ARP / Cosworth bolts are ftlb.