If you were to take a guess at the longest-running engines ever built, you’d likely name a few diesels, like the Cummins B Series, especially the 5.9, and some legendary V8s, like the Toyota 1UZ. You know, real heavy-duty stuff. But, if there’s one powerplant that may have claim to call itself king of the million-milers, it’s probably the Honda K24, a straight-four that carried more than its fair share of SUVs, sedans, and hatchbacks to seven digits.
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