Andy, others,
For the 7075 rods I've made for Picco engines, I've always put two oil holes at 4 and 8 o'clock, with none at 12. I have had no failures to my knowledge (feel free to correct me if I've forgotten) since moving to that configuration (initially, they were at 2 and 10, with some failures due to ripping the bottom lobe apart through one of the oil holes) . Upon receiving ALOT of requests for an oil hole at 12 o'clock, I finally conceded and added it, but have still had no problems that I recall, with the two oil holes at 4 and 8, and a slight groove in the bushing, front to back, at 12 o'clock to allow for distribution of the oil? I'm not here to promote my parts, I'm just wondering about the need for the top center oil hole. I can definitely see where it would put a fracture initiation point right where the pressure is highest.
Thanks. Brad.
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