Seems to be no hard and fast rules on this. On the older VW diesel engines, which use a TTY head bolt, the shop manual has a precise torquing procedure including a prescribed retorque at ~1000 miles or so. You tighten to 30 then 44 ft.lb. then 1/2 turn, run the engine to temp, then 1/4 turn on all the head bolts, then after 1000 miles, a further 1/4 turn. Yet, new from the factory, you don't do any retorqing.

r.c.brown@ieee.org
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Project: 4Crawler
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