Ferrari drivers Sebastian Vettel and Kimi Raikkonen both appeared unconcerned by the loss of track time on Friday as a result of heavy rain hitting the afternoon's free practice in Suzuka.
"We kind of expected it to be a wet afternoon," Raikkonen told reporters after the end of a truncated FP2. "We'd run a little more laps in first practice and it was okay.
"Everything felt fine so we have a good idea in the dry how it is."
The Finn added that there had been little point in completing anything more than an installation lap in the rain.
"We didn't even try to learn anything," he shrugged. "Obviously it's very limited on the tyres. In case if it's wet tomorrow and in qualifying then we have to save the full wets."
The forecast is indeed for more showers on Saturday. However the race itself is looking set for dry conditions.
"If it is tomorrow wet the whole day, we'll do some running in the morning."
Raikkonen has taken a new engine for the Japanese Grand Prix. It's the latest spec of the Ferrari power unit, which is reported to be lighter than its predecessor. However, Raikkonen said that he'd not noticed any difference in the limited running he'd had with it so far.
Raikkonen failed to start last week's race because of a turbocharger failure. Vettel started at the back of the grid after a similar problem in qualifying.
"I think we have a good understanding of what happened," Vettel said in Suzuka. "It has only been a couple of days but some parts went back and I'm pretty sure it shouldn't be an issue here."
Reports said the problem had been due to a carbon tube. The power units had returned to Maranello between Malaysia and Japan for service.
"We fixed the problem," said Raikkonen. "But no one can guarantee that it won't happen again."
Meanwhile Vettel will be using the same gearbox that he had in the car last weekend in Malaysia. The team checked it after his post-race collision with Williams' Lance Stroll, and decided it was undamaged.
Asked if he was concerned about its reliability this weekend, Vettel responded with a succinct "No."
"We will only find out after we put the gearbox on the car on Saturday, but judging from what I heard, everything should be fine," he said.
The four-time world champion was equally dismissive about the impact of the weather on this weekend's Grand Prix.
"I think it will be fairly normal. It should be fairly straightforward," he said. "I think we have a good chance.
"I don't think it matters," he continued, when asked about the impact of today's rain. "Let's see what the day, what the weather does tomorrow, what the day brings tomorrow and then we go from there.
"I feel the car was strong this morning, this afternoon we didn't run, so should be fine," he added.
Vettel had been fastest in morning, setting a top time of 1:29.166s in damp conditions. That had put him two tenths ahead of his title rival Lewis Hamilton in the Mercedes.
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