Reply to thread

Message: [QUOTE="V-Ref, post: 848377, member: 660"] Arisley....looks like you've been around the 7.3 a lot longer than I...but the used/new studs comment....I disagree with, and am afraid it might lead someone astray. The way I understand it....fasteners all have an elastic property to them...whatever the material is...from factory bolts to ARP 626 space age to A1 H11s....and the manufacturer tq rating that is specified for that fastener puts the fastener somewhere south of the Proof Yield on the graphic below. The reason you do hot retorques, is due to dissimilar thermal expansion characteristics of the fastener, the block/head, and the gasket itself in the case of head gasket. Without doing the hot retorques....you can't be certain the fastener is applying the same minimum clamping force at all temperature ranges. If you've "stretched" the fastener...this is indicitive of going past the point on the chart below labeled as "yield".... In the 7.3 world...it seems to be common knowledge that ARPs can't be reused, but A1 H11s can...This is :bs: either can be reused, as long as they haven't been taken past the point labled as "yield" on the graph below...you'd need to measure the length of the stud to ensure it's unstressed length on a used stud was the same length of an out of the box brand new stud. Or the mfg will have a specification on the length of "stretch" that is permissible, to ensure the fastener wasn't ever placed in condition that put in the "plastic" range on the graph below, and has always been in the "elastic" range. I hope this doesn't sound like Mr. Smarty Azz....just read your post above about stretched studs....and it conflicted with what I understood about fastener strength properties. I'm ready to learn if you've got knowledge/experience that states otherwise. :toast: [url]http://www.smartbolts.com/wp-content/uploads/2012/10/fastenal.tensile_stress-strain.jpg[/url] [/QUOTE]