Now that I have everyone's opinion, I have always done it the way Ian
described. Since I put in the hot s*it ARP studs I figured I'd get their take
on it. Al, from tech support at ARP, said that I should crack the nut loose,
then torque back, and do it in the normal order. This does make sense to me as
the reverse order would essentially mean torquing the head in the reverse order
which just doesn't seem right to me.
Having stated all of that, it is obvious that there is more than one "correct"
way to accomplish the re-torque. I think I will follow the mfg recommendations.
Thanks to all for your opinions.
Gordie
-------------- Original message ----------------------
From: Charles & Peggy Robinson <ccrobins@ktc.com>
> The way I learned it, after the engine heated up and cooled down, the
> head gasket would compress a bit but not evenly. So the idea of the
> re-torque was to even out the clamping force again. Some nuts/bolts
> would move a bit, some not, according to how much the gasket had
> compressed.
>
> Well, with the idea being to make sure the fasteners are stretched to
> the center of their elasticity range and that the clamping force on the
> gasket is correct, it doesn't seem reasonable to back the torque off
> first. IMHO, YMMV,
>
> CR
>
>
>
>
> mgamgb wrote:
> > Reverse order IS correct but one at a time. Un-Do approx. 1/4 to 1/2 turn
> >> (just so exsisting torque is defeated.). Retorque.
> >
> >
> > Retorquing the head studs is going to result in an increase in clamping
> > of the head to the block.
> > The effect is an extension of the same loading that is applied when the
> > head is first attached and the nuts torqued up.
> >
> > This suggests to me that the normal tightening sequence rather than
> > reverse sequence should be followed.
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