Mercedes has promised that it will continue to push to the very edge of reliability in 2018.
That's despite new rules limiting teams to just three engine units this season, compared to four in 2017. No team managed to completely avoid grid penalties for going over the limit last season.
But Mercedes believe that it can't afford to play things safe in the coming campaign if it wants to secure its fifth title.
"To be honest, we'll always be at the edge," Mercedes engine chief engineer Phil Prew told Motorsport.com. "You will always want to push the performance up to the durability of the power unit,"
"It's easy to turn down a power unit and find reliability," he added. "We don't want that. That's not going to win us championships."
Ferrari was Mercedes' closest rival in last year's championship. Renault were continually trying to balance performance and reliability. As for Honda, the Japanese manufacturer was besieged by problems on all sides.
Prew said that Mercedes' work on reliability had been and would continue to be "absolutely endless".
The manufacturer made substantial revisions to its engine throughout 2017, particularly in relation to the hybrid components. The result was the mos reliable engine on the grid last season.
Even so, Lewis Hamilton still had an engine change grid penalty at Brazil. It was a precaution after he crashed out in qualifying, meaning he was already starting the race from the back.
"We address every limitation, every component of the engine based on what it needs to do," Prew explained.
"If it needs to change, it will change to achieve reliability and performance. If not, then we stick with something we know.
"Everything is taken on a case by case basis, but the requirements are very clear."
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