Ferrari's power unit logged in the most laps in Week 1 of pre-season testing, but while Mercedes should have been a close contender for second, that runner-up spot went to Honda.
The Italian engine's tally, which came in at 6,931 kilometers over the course of the first four-day test, was delivered by the Scuderia and its two customer teams, Alfa Romeo and Haas.
While Mercedes also supplies three outfits, Williams only accounted for a small amount of the recorded mileage in Barcelona because of the team's late start to its FW42 test programme.
But even the late addition of the Grove-based outfit wasn't enough to put the German manufacturer second.
Honda, with its two teams, Red Bull Racing and Toro Rosso, enjoyed rock solid reliability that allowed it to put 4,454 kilometers on the board during Week 1.
Renault, with its works outfit and McLaren, accumulated 4,087 kilometers from Monday to Thursday.
Overall reliability has been very good for all teams since the start of pre-season testing.
But to the best of our knowledge it's been flawless on the power unit front, with no engine failures to report, although there may have been preventive component changes behind closed doors between sessions.
Regardless, the solidity of the various manufacturer's power plants bodes well for the season ahead.
(Thanks to Motorsport Stats for the chart)
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