Lewis Hamilton and Valtteri Bottas will be powered by an upgraded Mercedes power unit in this weekend's Belgian Grand Prix at Spa-Francorchamps.
Mercedes boss Toto Wolff said earlier this week that the team's High Performance Powertrains unit at Brixworth had worked throughout the summer to deliver more performance and reliability to its engine.
While a bit more muscle will be required to fight Ferrari on Spa's long straights, Hamilton insists the update won't bridge the gap with the Scuderia in terms of sheer output.
“It’s pretty much the same as the second one, so not really any real improvements," said the Brit.
The upgrade will also extend to customer teams Racing Point and Williams.
Hamilton and Bottas should not receive any grid penalties following the change, unless the Finn's engine is also fitted with new control electronics or energy store elements.
However, Racing Point's Lance Stroll will be demoted on Sunday's grid for exceeding his 2019 three-engine limit, a result of a power unit failure incurred by the Canadian in Montreal.
As a reminder, Honda has opted to supply a Spec-4 upgrade unit to Red Bull's Alex Albon and Toro Rosso's Dany Kvyat.
Both men will be sent down the order on Sunday's grid following the change.
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