Fernando Alonso says Ferrari are in the dark about the Korean pecking order as they refused to compare their pace on Friday.
Alonso is in desperate need of a great result this weekend in Korea after watching his lead in the title slashed to just four points when he retired at the previous race in Japan, which was won by his main rival Sebastian Vettel.
Worryingly for Ferrari, the Red Bull racer was again in form at the Yeongam circuit on Friday, setting the pace ahead of his team-mate Mark Webber while Alonso was third, 0.328s down.
The Spaniard, though, did appear to have good race-pace, matching the Bulls and McLarens over long distances.
However, whether he reckons Ferrari are in the pecking order Alonso isn't saying.
"It's hard to say where we are compared to the others, because today, we focused mainly on ourselves, working this morning on a comparison of various ideas relating to car configuration and, in the afternoon on the tyres," said the 31-year-old.
"We must wait til tomorrow to have a more precise picture of the situation."
The drivers also made to contend with a very dirty track on Friday, which steadily improved as lap by lap the drivers cleaned the dust.
"The track improved a great deal from one session to the next: it's a phenomenon that's particularly accentuated here, because there's hardly any racing on this track and this morning, it was particularly dirty.
"Let's hope the situation improves for tomorrow because it's always more fun driving when the track offers at least some grip.
"The most demanding part of this circuit is definitely the third sector, the shortest in terms of time, made up almost entirely of corners.
"The set-up choices are dictated mainly by car behaviour in this third sector, while the other two are definitely easier to deal with."
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