Raikkonen and Vettel cautious over Ferrari engine upgrade

Ferrari drivers Sebastian Vettel and Kimi Raikkonen topped the opening two free practice sessions at Spa-Francorchamps on Friday ahead of this weekend's Belgian Grand Prix.

"That was our first day of practice after the break," said Raikkonen. "We did our pretty usual job to get a feeling for the car once again. I enjoy driving on this track, it has a good flow and this generation of cars are pretty nice to drive here.

"We always say that Friday is Friday and times don’t really matter today; it was okay, but for sure we still have some work ahead of us," added the Finn after setting the fastest time of the day, clocking in at 1:46.533s which put him 0.168s clear of Mercedes' Lewis Hamilton.

That was with the aid of the latest upgrades to their power units, which had been rolled out to customer teams Haas and Sauber at the previous round in Hungary. Raikkonen said he wasn't expecting the new components to make a huge difference this weekend.

“Obviously we never put in the car anything we don’t think is a bigger step forward or better so it’s not possible to say," Raikkonen said.

"It’s not a night and day difference ever," he said. "Otherwise you could see by yourself if that was the case.

• Raikkonen keeps Ferrari on top in Spa on Friday

“For sure [the car] is better than the last time I won here. That was not a very strong car, but it came better at the end."

Vettel was similarly wary of how much performance boost Ferrari could expect to see this weekend, and at the next round in Monza which is just as much a power-intensive track as Spa.

“It’s a bit difficult to know already,” Vettel shrugged. "We’ll see what the next two weeks bring. For now, everyone seems quite happy that the engine is doing what it’s supposed to do.

"We need to have a look, but on that front I think everything was working," he said. "But it is only Friday so you cannot tell anything. Let's wait until tomorrow."

While Vettel topped the morning session, he struggled to get a clean run after lunch and finished only fifth fastest.

"Kimi maybe was a bit happier on one lap," he suggested. "But we still have a bit of time.

"Today has been okay. The car felt not yet where I want it to be. I think we need to do some work.

“We have a bit of margin [but] there’s quite a bit more in the car. I need to make sure I get to it tomorrow.

"Here it's important to be confident to get the right timing as there isn’t much time to think, when to turn in and so on because the cars are quite fast.

"It needs to click. On one lap, it didn’t click. But overall it’s going in the right way."

Vettel was also concerned about the prospect of wet weather on Saturday, with FP3 looking set to be bit by rain. He crashed out of the German Grand Prix while in the lead when he was caught out by showers but felt that the team had worked to address any issues with wet conditions.

“I think we had our weaknesses in the wet but we have worked on those," he said. "We understood those so if we have wet conditions it will be quite nice to confirm and see whether we found the right things.

"On this track everything seems to happen faster, so it should be a lot of fun and if we have dry conditions tomorrow for qualifying, we should be okay."

Vettel also signalled his hope that Ferrari would retain Raikkonen for another season.

"It's not for me to judge, but we get along well and have no issues together. It's up to Maurizio [Arrivabene, team principal] and the team to decide."

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