While the big end grinding may not be eye appealing, the cap strength hasn't been compromised. I would be more concerned if they still had stock rod bolts. Reciprocating weight to rotating weight is commonly 50% but even that is often changed higher or lower in some applications.
Randy
"May not be eye appealing", now that's being very courteous of you Randy
, but with my experience with the aircraft engine industry, they would absolutely blow a gasket if I handed that sort of workmanship to them (oh, and don't tell, because I'm not a certified FAA repair facility, but I have done some balancing work on a few aircraft examples, mostly for racing applications which are often categorized as "Experimental" which means all is O.K.); and as I do realize that that connecting rod may never be installed in anything that leaves the ground (for any duration anyway
), you would have to agree that it is less than ideal to be creating all of those stress risers via the grinding striations, particularly across the cap beam.
What, you don't like that scrawny shank, screwed-up, interference tread bolt? But another concern is the fact that many of the "Lemans"rods do not exhibit proper beam/cap location via the dowels, as excessive clearance is often present in the counter borings to dowel fitment.
And yes, adjusting the "bob-weight" values is often changed to greater or lesser sums, as in reality, nothing is balanced absolute (even the Earth wobbles). My favorite example are particularly the "Brit-Twins" bike guys, who provide specifications for reciprocating sums for their Nortons ,Triumphs, BSA's etc. varying from if I recall 48% to as much as 82%, as one must just accept it's going to vibrate, just at what R.P.M. do want the mirrors to be a blur and hands (and maybe not the only thing) go numb.
Scott.