Caterham pair disappoint in Silverstone qualifying
Vitaly Petrov and Heikki Kovalainen posted the 19th-and 20th-fastest times, in a session where Caterham had hoped a revamped car would give them an extra half-second of pace.
But the dreadful weather conditions, with rain on one part of the Silverstone circuit and other parts untouched, ended up mitigating any advantage the car's new bodywork and exhaust might have offered.
"Today the conditions weren't fantastic," Petrov said in televised comments. "It was very difficult to drive. You don't know how much you can push."
But Petrov outqualified his teammate for only the second time this season.
"This is the priority," he said. "First of all I must beat my teammate."
McLaren's Jensen Button was a surprise loser in the first session, finishing one place ahead of Petrov.