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A circuit track would count ase extended use. The biggest difference is that while a drag engine will see enormous rod forces, the track engine will se full power for much, much longer time without chance to really settle down in between, also the engine may be over revved past the shift point because of track topology and so on.
When the rod is run at great load, the material will absorb a part of the mechanical energy, and the energy can cause alterations in the metal properties. On a drag car, the engine only needs to provide full power for a number of seconds, and is then let cool down. On a track, even one lap will take minutes and have a large portion of it driven at full power. The process is partially reversible, but the amount is rather a constant number rather than percentage; in a drag engine, the reversibility will cover most of the alterations, but after a long and heavy run, the same amount of reversibility will only recover a small fraction.
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