Ford fitted the lowest costing bolts that would survive the intended application. High grade steel and rolled threads cost alot more - and were avoided purposely. ARP type bolts are infinitely superior to factory stretch bolts. However, factory stretch bolts do perfectly fine in many applications. The Ford CVH head (and its poor flow compared to modern 4 valve designs) limits power output, thus factory stretch type bolts may be successful. I however choose not to use factory hardware - head bolts and main cap bolts. Why spend $10,000 on an engine build and use 10 cent bolts?

Torque spec for ARP bolts is 60 ft. lbs. with ARP thread lube.
Retorque bolts after engine has been warmed up and cooled.