Re: How are bolt torque specs arrived at?

hls wrote:
> 
> "C. E. White" <cewhite3@[EMAIL PROTECTED]
> wrote in message This is 
> done using specialized machines
>> that sense a change in the stress strain relation****p as the bolt 
>> reaches the yield point. This is a very good way to torque bolts for 
>> variable loads, but difficult to duplicate in a repair environment.
> 
> 
> I have seen bolt elongation gauges advertised and recommended for 
> performance
> engine building.  They are not so expensive.
> 
> I have never used one of them, and wonder if anyone here has any 
> comments on
> them.

I've use them on sbc rod bolts.  Arp gives a couple of torque values 
(depending on the lube used) and a stretch value.