Mercedes’ new engine is worth up to two tenths per lap in extra speed.
That is the news from Mercedes team chairman Niki Lauda, as the reigning champions confirmed that after a one-race delay, the ’spec 2’ power unit is now ready to debut at Paul Ricard.
"We are a race late but I am told that the new engine version is now in use," F1 legend Lauda said in France.
Lewis Hamilton, fastest in both sessions, used the new engine in Friday practice and said it felt "clean and fresh".
Lauda said: "The difference can be one or two tenths."
Earlier, the great Austrian said it was "clear" that on recent form, Ferrari now has the fastest package in F1.
Lauda continued: "No one knows what the others are doing, so I just hope our engine works well here.
"It’s important so that we can get back to pole position.
"We are running late with the new engine because we really wanted to be sure. But Andy Cowell is doing a perfect job.
"What I hope is that our engine helps us to come back, because everyone else improved at the last race," he added.