Aren’t they all hard parts failures? The cause, however, we can only speculate on. 20psi isn’t a lot of boost, except in the case of a 40 year old stock block so who knows. It could have let enough oil in the chambers where even the best tune wouldn’t have mattered. He could have easily found the threshold of too much timing at peak torque for those rods as well. Pretty hard to tell the root cause from a video. Still, pretty cool to see.