Re: [DML] Angle Torque & head bolts

[mike.griese@xxxx]

This falls under the "just don't do it" rule
of auto mechanics. Head bolts are cheap compared
to what can happen if one fails. Just don't reuse 
them.

Measuring torque on a fastener is an indirect method
of measuring the amount of tension applied to 
the fastener. It's an approximation, since there are
a number of factors that influence the torque reading 
on a wrench. The condition of the threads, the 
condition of the surfaces of the bolt head and nut,
any lubricants on the threads, thread locker or 
anti-sieze all have an effect on torque readings.
Measuring angle torque removes a lot of these other
influences. The angle the fastener is rotated
is a direct measure of the stretch in a bolt because
the thread pitch is known. In racing applications where 
both ends of the fastener are accessible, mechanics actually 
measure the length of the fastener before torquing and
after to ensure the correct amount of stretch is 
achieved.


--
Mike

> When reattaching the head, the manual recommends that once they're torqued
> to the proper setting, you should angle torque 113 degrees. I've been
> researching angle torque and have a pretty good understanding of it now but
> what I'm wondering is if anyone has actually applied this method?
>