In a message dated 9/22/2006 2:47:24 PM Central Standard Time,
rgperry@earthlink.net writes:
> I may start a lively discussion with my opinion about the frame members
> cracking after installing tube shock conversion brackets, so here is my
>opinion.
> I believe that the problem of cracked frame members is due to the
> relocation of the fulcrum point from between the two mounting lever arm bolt
>holes to
> a point extended at the end of the shock mounting bracket. This distance
> change between the old and new fulcrum points acts as lever multiplying the
> forces applied to the original lever arm shock point. Thus increasing the
>force
> applied to the differential cross member beyond what it was engineered for.
> A basic analogy would be when one is applying a cheater bar on to the end of
> a breaker bar to provide more force to break a bolt or nut loose.
>
> Disclaimer Notice:
> I am only expressing my opinion on the reason why sometimes the frame cracks
> after installation of the tube shock conversion brackets, not about the
> benefits or deficiencies of installing the tube shock conversion kits on a
> vehicle.
>
And my opinion is quite different. Since the eventual point of force
application remains the same (the end of the trailling arm) the net forces
applied to
the shock mount doesn't change. If you add up all the force vectors the
major vertical vector contributed by the shock bracket is negated by the
vertical
vector of the telescopic strut.
On the othe hand, since the telescopic shocks are much more effective at
dampening movement than the lever shocks the net forces applied will be higher.
But this has nothing to do with geometry.
Dave
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