Stock rod bolts were used. I believe that the bolts failed on that one and ejected the rod cap then the crankshaft took the rod out while it was hanging. Something was going on with that piston/pin/rod since the pin had slid out, I put that piston on the rod with the same wrist pin that had always been married to it. Was driving towards a stop sign at 10mph when this happened, a knock started and within three seconds it let go. I drove it two miles home then.Where those stock rod bolts? Did the rod fail and shear the bolts, or did the bolts fail and break the rod? Hard to determine the cause.