how many times can you reuse stock head bolts?

Fasteners that provide their clamping force below the yield point (all ARP fasteners work this way; this thread is inconclusive about which stock Mustang head bolts are non-tty -- at least 4 different opinions have been offered about the year break) can be used more than once. Tightening them to the torque point does not yield them - they simply act like a spring that 'springs' completely back to their original shape once the torque is removed. Measure them before and after torquing, and they are exactly the same length.

Torque to yield bolts are called that because the process of tightening them actually yields the metal - that is it stresses the metal PAST it's yield point. If you were to measure their length before and after torquing them in the proper way, they are longer after they're torqued - they literally are stretched and cannot 'spring' back to their original shape/length. Once yielded, TTY BOLTS CANNNOT BE USED AGAIN SAFELY - they are not capable of providing the clamping force needed to secure the component.

SO my Ford book is wrong???????????

Not all V-6's use torque to yield bolts.The 2.8 in my Bronco II has re-usable ones.When I put on head gaskets I clean the head and block with brake cleaner so there is no trace of any oil and I put them on dry with no sealants.I have always done this and have never had a problem.

Don't know what your Ford book says Mr. C; but I do know that any source that suggests reusing fasteners that have been yielded is doling out harmful information.

i beleive 91-93 is torqued to yeild, earlier years were not torqued to yield, check a book

What if someone has already swapped head bolts out of that car before??
why take the chance this really shouldnt even be a discussion buy some new Head Bolts (ARP) And save your self the worry,And time of having to do it all over again if they fail.

"if your going to do something,Do it right the first time!"

For those of you that want to learn more, go to the link - an excellent primer on Torque-to-Yield bolts and the mechanics behind them.

http://www.robbos.com.au/myweb/Tech_Bolts.htm