Ferrari used its customer teams to give its latest specification Formula 1 engine its debut in Belgian Grand Prix practice.
The works Ferraris of Sebastian Vettel and Charles Leclerc are expected to take the new unit in Italy next weekend.
Haas pair Romain Grosjean and Kevin Magnussen and Alfa Romeo driver Antonio Giovinazzi all ran the engine in first practice at Spa on Friday morning.
All three drivers who changed took a new V6, turbo and MGU-H.
None of them will receive any penalties, as they are still within their season allocation of three elements, and the works cars will also be penalty free when they change to the new unit.
But Alfa's Kimi Raikkonen will receive penalties when he makes his next change, as he has already used his allocation for all six elements.
Six drivers on grid penalties already
Although the Ferrari users have escaped penalties, six other drivers will take grid drops in Belgium this weekend.
Nico Hulkenberg, Daniel Ricciardo and Carlos Sainz Jr have all taken the latest Spec C Renault V6, and will receive five-place grid penalties.
Alex Albon, Daniil Kvyat and Lance Stroll have all taken multiple new elements and will therefore go to the back of the grid.
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