Lotus will stick with its long wheelbase car for the remainder of the Korean Grand Prix weekend after an encouraging opening day of practice.
Although Kimi Raikkonen's day was interrupted by a high-speed crash at the end of first practice, Romain Grosjean ended the second session with the sixth fastest time.
The team has faith that the tweaks to the car - which were tried for the first time at the Italian Grand Prix - deliver enough of a boost for it to be worth committing to for now.
Grosjean said that he could not feel where the car was a step forward, but that was probably due to the fact that there was no opportunity to conduct a proper back-to-back test.
"To be honest, I don't feel any difference so we should be alright," said Grosjean. "It is on paper supposed to be more stable on high speed and the entry of slow speed - but it is hard to say when you get in the car and drive it.
"It is not like we could have done a back-to-back to see exactly what the differences are. In general, we don't have to complain about the car too much."
Raikkonen believes that things were heading in the right direction for the team, despite his crash.
"It didn't help that I destroyed the car this morning, so there was a hurry to fix it," he said.
"I think it was okay. The long run seems to be fine, but on the short run it is not exactly how I wanted. But I think I made in the end a good car, just a bit faster."