Re torqueing head studs/bolts

We're saying the same thing.....BTW the extra torque needed for 'breakaway' is due to stiction which is always higher than the friction of moving. It is like sliding a heavy box along the floor: you need to put more force on it to get it moving and it takes less force to slide once it is moving.

That's the classic definition of static vs dynamic torque. ^^^

As far as the bolts stretching, the old original types in these engines can be re-used because they are not designed to stretch beyond their elastic limit and become permanently stretched when torqued to spec. (Although some may indeed permanently stretch at times.)


Even the old ones stretch a little at a time when torqued. I still would not use them over 5 times. I have a rocker arm bolt that is stretched to where you can see it necking down in the threads. If it is used and torqued, it's sure to break.

I would not take chances with critical bolts like rods, mains, rockers, and heads. 5 clamp cycles and throw them away or use them for mock up only and replace with new when done.