Mercedes has delivered an upgraded engine to its customer teams in Canada, Force India and Williams.
The new-spec unit had already been introduced in Spain and used exclusively by works driver Lewis Hamilton while Valtteri Bottas recieved the upgrade in Monaco.
"I think it’s more to do with reliability than outright performance," said Force India COO Otmar Szafnauer.
"The outright performance stuff comes from the fact that you can run it for longer in a more performant mode. But if you’re asking about laptime, it’s nearly the same.
"We can run some of the more performance modes in the race longer, so the race time is shorter – but over a lap, it’s the same."
Both Force India and Williams now have an allocation of three engines to cover 14 races, a status which means the teams won't need for each engine to cover five races, theoretically allowing drivers to push the boundaries of their unit.
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