Lotus' latest chassis was always scheduled for arrival at the Valencia race, and Kovalainen had been pencilled down as the man to get it.
However, with Trulli having complained of balance problems with his usual car, technical chief Mike Gascoyne reckoned it would be in the team's interests that the Italian gets it instead this time.
When Trulli was told what has happening, however, he said he did not want the new chassis because it was not fair on Kovalainen.
"Jarno has been pretty unhappy with the balance of his car and has been struggling," Gascoyne told AUTOSPORT. "We have a new chassis scheduled to come for Valencia, and that was due to go to Heikki.
"But, because of Jarno's troubles, I made the call to change it to him. But Jarno, when he was told, said, 'No, I don't want Heikki to feel that I am being favoured, please feel free to give it to Heikki.'
"So I went up to Heikki and told him. Then he said, 'No, Jarno is struggling, give it to him!'
"It's a situation that sums up the great feeling within the team - that they are both trying to help each other. In the end we are going to give it to Jarno, but the two drivers are open to swapping it around afterwards."
