The championship leaders first tried the significant upgrade at Silverstone two weeks ago but pulled it before SaturdayÃ¢â‚¬â„¢s qualifying session, intending to return it for free practice at Hockenheim.
McLaren endured a difficult first day on Friday as rain lashed down to prevent the team from collecting all of the required data.
The Woking-based team were further hampered by Lewis HamiltonÃ¢â‚¬â„¢s collision with a tyre barrier in the first session, leaving mechanics frantically working on the championship leaderÃ¢â‚¬â„¢s car for most of the second session while Button took to the track.
The team, however, are happy with the data from the running in FP1. Ã¢â‚¬Å“The main peak airflow, the gas flow from the exhaust, temperatures, the performance, and the pressure tapping velocities were what we expected them to be,” team principal Martin Whitmarsh revealed.
Whitmarsh also confirmed that the team were able to rebuild HamiltonÃ¢â‚¬â„¢s car to its pre-crash state despite damage sustained to all four corners.
It also ended any speculation of HamiltonÃ¢â‚¬â„¢s quicker lap time being down to him running the old floor, with Jenson Button concentrating on high fuel running.
In a strategic move, HamiltonÃ¢â‚¬â„¢s only run came on the slower prime tyre, which makes his 7th-quickest lap all the more impressive.
Based on the lap times from the limited dry running, McLaren donÃ¢â‚¬â„¢t appear to have the pace to compete with Ferrari and Red Bull as their rivals battled it out for the quickest lap in second free practice.
How well the new blown diffuser works on a long run remains to be seen, but if it does most of what the team expects it to do, McLaren should certainly have the ability to win on Sunday.
The championship leaders are not always quickest in qualifying, so not making it to the front row will not be a disaster. Their pace off the line should make up for any qualifying disadvantage.
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