i did have some deck damage in the past due to steam. i solved it by upgrading the center studs to 9/16ths. the torque value increased from100 lbs up to 130lbs. going higher on a cast block can pull the threads. this seems to have fixed that issue. the failure this time just seems to be simple rod failure. the crank and bearings were not black. the rod bolts were not broken. the piston was not stuck. that pretty much narrows it down. i dont think a lifter failure could cause this damage. although in a nitro engine anything is possible. its not a matter of if something will happen but more of how bad and when something will happen.