Lewis Hamilton admitted that things hadn't quite gone according to plan in Friday's practice sessions for the Belgian Grand Prix at the Circuit de Spa-Francorchamps.
The Mercedes driver finished a rain-hit FP1 down in 18th place after his planned fast lap hit traffic in the final sector while looking on course to set the best time before lunch.
He was subsequently third fastest in the drier afternoon session, just 0.072s behind pace setter Max Verstappen, but insisted that he had work to do after finding the car still wasn't quite how he wanted it.
"We were trying to navigate the best way we can," Hamilton told the media afterwards when asked about his approach to the day. "At least it was dry for FP2 so we got some laps in.
"But the car wasn't quite underneath me today," he admitted. "It's also tough to gain knowledge in these short sessions ... I've got to do some work tonight and try and figure that out."
The challenge for all the teams this weekends is to find the right combination of downforce settings and engine mapping that allow the car to cope with Spa's sweeping corners without losing too much speed down the long straights.
"It's massively challenging circuit to try to find that balance," Hamilton agreed. "This morning we had it one way. We changed it this afternoon. It was very, very similar [in terms of overall lap time].
"You try one option and you are faster in the first and third sectors but slower in the middle. And then you try the other option and it's the opposite. So figuring out the right balance is really tricky.
"The weather is also going to play a big role. If it does rain, you obviously want more downforce. But then if it doesn't rain, you are a sitting duck on the straights. So we have to be very careful with the changes we make.
Hamilton was also surprised to find that the track had changed since his last race here as a result of serious flooding in the Ardennes region.
"It's very bumpy now through Eau Rouge, something's happened and they kind of ruined it a little bit," he said. "There's a massive bump right at the compression point which we've never had there before.
"It's really, really sharp and you feel it on the backside," he added. "But I'm sure they'll fix it I think it has something to do the mudslides, or the rain."
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