Just looks like the parting line was ground down on one and not the other. On rods that have been properly prepped, the line is completely smoothed with a belt sander to eliminate any stress points on the surface. Most all connecting rods were forged. The "Cracked" connecting rods of today are powdered iron. Cheap to make and not very strong.
All of the other 7 rods look the same, ground off parting line, all the rods were stamped 1 through 8 except number 6, I believe this is number 3 with the narrow line. I was just concerned about it. Want this 340 build to be right.
