Kimi Raikkonen was much happier with his F14T on Friday but admits there is still a long way to go.
Returning to Ferrari this season, the 2007 World Champion never felt entirely comfortable in the car during pre-season testing.
This continued into the season-opening Australian GP where he was unable to take to the fight to team-mate Fernando Alonso.
That, though, changed on Friday in Malaysia.
Raikkonen posted a 1:39.944 to finish second quickest, just 0.035s slower than Nico Rosberg, while Alonso was fifth quickest.
"I had a better feeling compared to Friday in Melbourne," Raikkonen said.
"I was more comfortable with the F14 T today and even if we had no problems whatsoever, we know there's still a long way to go and a lot to do.
"Our programme concentrated on car set-up and on testing the compounds that Pirelli has brought here.
"The handling seemed to be good even if, as we found on the race simulation, we will have to pay very close attention to degradation, which is particularly high here.
"Now we will spend the evening carefully analysing all the data we gathered over the day, to try and work out how to improve."