The press-fit crank hub: the signature S55 concern

The factory press-fit crank hub is the most-discussed S55 weak point, able to slip the timing gear on high-torque or tuned cars (commonly cited past ~525-550 WHP) with damage ranging from a CEL to piston-to-valve contact; most owners treat it as overblown on stock, unabused cars, but bidders still routinely ask whether it has been addressed.