"Pink" versus PM rods

[Daniel Burk]

Gary,

The Pink rod is NOT stronger than the powdered metal rod; at least
according to GM.

The PM part has better weight distribution, no casting flash, smoother
finish, and is also harder than cast iron.  Newly designed rods can also
be pressed as a one-piece unit, including the rod end. The end cap is
then "snapped" off such that when re-attached, the crystalline pattern
acts as a retainer, thus easing side-loading of the bolt. The bolt need
only to confine forces in which the vector passes up the longitudinal
axis of the rod.  The rod itself constrains the other forces!  Of
course, you can't mix & match rod caps with other rods.  I am unsure if
the LT1 rod takes advantage of this, but the '99 Ford modular V8 is
slated to use this technology.

One other advantage of PM rods might be in their weight variance. They
may be more homogeneous and require less balancing.

A point of trivia: A PM part is porous. As such, it can be impregnated
with oil, which may aid in lubrication of the wrist pin and/or crank
interface.

    --- Daniel Burk