Caterham's drivers believe that the true potential of the significant upgrade package the team brought to Silverstone has yet to be identified, with all but one session so far this weekend being run in wet conditions.
Caterham introduced a new engine cover, turning vanes on the sidepods and bargeboards, moved back the radiators, added new brake ducts and tweaks to the floor as part of the package.
But while both Heikki Kovalainen and Vitaly Petrov were unable to make out of Q1 in qualifying, they reported that the changes to the car had worked.
"I think more or less we know we have much more performance to take from it, but [in qualifying] the conditions were so difficult to show the maximum performance from the car," Petrov told AUTOSPORT. "It is quite positive, although the conditions were not as expected, but more or less we are happy and what we are happy about is our aero package working well, and this is important.
"We still maybe are a little bit not understanding how to make it work well so in the moment... But we feel the step.
"It is difficult to understand but when they put new wing and aero package, I felt the balance was completely different. In P1 and P2 I said go down with front wing. Normally you have understeer. Here instead it was sharp - I was not ready for it. I felt this was something!"
Kovalainen admitted he had been disappointed not to make the jump out of Q3, but added that it may be the German Grand Prix before Caterham can extract the new package's true performance.
"I think it's difficult to say ultimately how well the update is working because we haven't run it in the dry enough," he said. "Of course I was hoping for more in qualifying. Again in these kind of conditions you think you might have a chance to get into Q2, but of course I was hoping for much more and in the end we were not even close to get into Q2 - there was quite a big gap so that is disappointing.
"But the positive thing is the update seems to be working. [To see] how good the update is in the dry condition I think we need to probably wait until Hockenheim. I'm happy that it's working.
"Today it is difficult to read into the gaps of the cars we have a head of us, whether that's realistic or not," he added. "I don't know, it's tough to say, but I think we are very confident they are working - maybe not perfectly optimised but they are not too far off."