"Pink" versus PM rods

[Joe Boucher]

Gary Derian wrote:
> 
> John Lingenfelter, in his new book, noted that he has seen failures in the
> new PM rod which he had not seen in the old "pink" rods which by the eay are
> forged steel not cast iron.  I know GM claims the new rod is better and
> there are advantages of PM construction and modern CAD designs.  I was just
> relaying Lingenfelter's comment.
> 

The PM rod construction is dependent on a new process to GM.  It would
be expected for them to encounter some problems with consistantly
pumping these things out without some bad ones getting through.

The formation of the rod cap by breaking it off is an indication of the
PM rods having less stretch or elasticity compared to the forged rods. 
Not necessarily bad.  The machine must impart a crisp wack to the sucker
when it breaks it.  Probably a silly putty reaction phenomenom.

If these rods are porous, I wonder how much weight it will pick up after
soaking in the oil?  Maybe a few grams, I would bet.

Joe Boucher
'70 RS/SS Camaro  '81 TBI Suburban