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Rods tend to break when revs are high on a closed throttle. There is no pressure holding the pistons down, inertial load increases and the rod snaps. This is why sometimes an F1 engineer will tell the driver to only use full revs with full throttle. Paradoxically this gives the con rods an easier time.
RR had the same issue in WW2 with highly blown Merlins. The pilot was required to drop the revs before dropping boost pressure (closing the throttle) or have the engine explode. Max revs were also limited in part boost.
Munkel's engine was so badly wrecked its impossible to say if the rod snapped and separated the big end bolts or the other way around. But with the holes being above the crank its most likely the rod snapped and the broken end punched out the cylinder block. The big end bolts failing (milliseconds) later. At 600 revs the pistons go up AND down 100x per second.
For tensile strength go with forged alloy steel.
RR had the same issue in WW2 with highly blown Merlins. The pilot was required to drop the revs before dropping boost pressure (closing the throttle) or have the engine explode. Max revs were also limited in part boost.
Munkel's engine was so badly wrecked its impossible to say if the rod snapped and separated the big end bolts or the other way around. But with the holes being above the crank its most likely the rod snapped and the broken end punched out the cylinder block. The big end bolts failing (milliseconds) later. At 600 revs the pistons go up AND down 100x per second.
For tensile strength go with forged alloy steel.