http://www.arp-bolts.com/Catalog/Cat...talog_0024.pdf
ARP on line. Page 24, 25, 26 gives bolt torque specs.
Also at the top of page 33 it gives the procedure for calling ARP TECH and the tech line numbers of some rod mfg's that use ARP fasteners.
http://www.arp-bolts.com/FAQ/TorqueStretch.html
If they are old and you don't know their torque history it might be safe to change them.
It's just a thought, but someone else could have used the wrong torque spec in their life cycle. ... ??