Anybody break a stock block, if so at what hp?

A well prepped 340 (non stroked /reworked 3.31 factory stroke crank/ factory WELL REWORKED factory rods/thick deck Arias ,loosely fit old product (think ,like 82..) /.030 over, was taking a 250 hit 20 years ago. ( low10's@ 128-130) Single Holley 950 H.P., traditional Dick Landy/Direct Connection fuel system modified. Never broke.. Spend duckers, on the machine work, don't get stupid on tune.