Harmonics split the block, the casting is thin in the webbing above the crank up to the cam. With an imbalance on the crank being slung around the forces are immense at 6k rpm, add to this the increased cylinder pressures ect and the main caps begin to "walk" this slight twisting action accompanied by the harmonics are what fatigue the block material and eventually cause a failure.
beyond that no matter how well the engine is built, designed or what parts used detonation will wipe it out quickly. once the wall of fuel is consumed in the chamber parts go by by...
as for our new friend,
@TheLeech405 I would love to discuss some of the techniques you use to increase longevity. I have been successful myself in making big power but I do not post about it. I let my customers do that for me. I have found any knock sensor completely blind at WOT conditions on a modified engine with any significant internals or mechanical cam. Unless there is some holy grail system you prefer to use, some are significantly better than others.
As for ignoring everyone but yourself, thank goodness you graced us with your presence.
Its not a stock bottom end, but a stock block... our nitrous car does 5.XX at 120 in the 1/8th so yes it is very possible.