always done header bolts nice and tight with a 1/4 turn. i work for ford look up a few thing for you and found no specs. retorque after they get hot and cold fro a while

thanks guys

The proper method to dealing with Ford problems is to remove the 8 bolts holding the engine into the boat, pull the engine out of the boat, find an acceptable sized dumpster, deposit said motor into dumpster. Add Chevy. Problem solved 

Oh Stop it! LMFAO! 

Problem I had with Moo's headers (Way to big of tubes to get a decent wrench on most of the bolts) was finding them later in the bilge after a hard days running. Some were just loose, they couldn't fall out (all the bolts, save a couple, had to be put on together and tighted simultaneously). I've been told NOW they are blower headers, Whatever THAT means.

I Was putting red loctite on them each time I found one or two and tightening them as best I could. Over last year, I think I managed to get them all.

Ray

If you don't want your headers to come loose put in longer studs and double nut them.
Period.  No more coming loose.