I have NEVER bought a new headbolt. I did twist one off because of dirt or
rust in the hole but it came out easily. I replaced it with a used one.

If your headbolts and capbolts don't appear stretched or damaged (ESPECIALLY
in the threads) I'd go ahead and use them.

Volvo headbolts are very good bolts so you need to replace them (if you have
to buy new ones) with grade 12 bolts, same is true for capbolts.

The OEM bolts are reduced section in the shank to I would prefer them to
regular fastener center bolts. (In fact I would rather use an old OEM bolt
than a new general purpose high strength bolt of equal strength.) They also
have bigger heads, which gives a better bearing on the head top surface.
--
George Downs Bartlesville, Heart of the USA!