In a message dated 3/31/99 7:35:44 PM Pacific Standard Time,
ttarleto@ix.netcom.com writes:
<< Talk of bolt stretch , ect is of course correct , for most bolts. There
are some bolts and nuts that are different, and lugnuts are one. The
clamping force of stock lugnuts comes fron the taper on the nut and wheel.
This wedge adds lots of clamping force to the wheel, and also increases the
friction of turning the nut. What this means is it takes more torque to
tighten the nut.
This means that 85 ftlb does not stretch the bolt , and as lug nuts are
hardened more that most nuts, the nut is not streatched either.
So lugnuts will last a long time. >>
So let me get this straight, when the local Yo-YO at the tire store hits your
lugs with a 300+ lb. ft. air wrench the stud is really not stretching when it
breaks, it is just a physical phenomenon that it lets go? I don't want the
impression past on to especially the Neon and Miata competitors that the
100 lb. ft. recommended torque setting and taking the lugs on and off
repeatedly, as in autocross, is not something that they can just consider
as having no impact on the nuts and studs. It is just simply not true.
It would be one of the items that I would check stretch at least at the
beginning and end of the season and probably change studs and nuts at
the end of the second season one way or the other.......small investment
to avoid a big embarassment and potential accident.
Tracy Sandberg
Sly Fox Racing
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