Ferrari's Kimi Raikkonen ended the final day of the second in-season test from Silverstone quickest, posting his best lap in the final hour of the session to jump straight to the top of the timing screens.
The Finnish driver's 1:30.665, posted on the soft tyre, was more than half a second quicker than Mercedes youngster Esteban Ocon could manage, despite having led for much of the day.
Ocon did however lead the lap chart with 139 to his name, 12 more than the second Mercedes driven by Pascal Wehrlein on behalf of Pirelli.
Red Bull's Pierre Gasly was third quickest as he completed a second day of running in the RB12, seven-tenths down on Raikkonen's best time, and one of six drivers to surpass the 100-lap barrier.
Also enjoying a second day of running was Force India's Nikita Mazepin. The Russian securing fourth place, albeit with the Supersoft compound, completing just 69 laps, the fewest of any driver. It was however enough, along with Tuesday's running, to secure a Super License.
McLare's Stoffel Vandoorne was fifth quickest, earlier noting how different the car feels to the last time he drove it during the first in-season test in Spain. He finished ahead of Williams' Valtteri Bottas in sixth.
Williams' rather unusual double-decker rear-wing made a return as they aimed to better understand the car's balance and tyre wear. The part isn't however legal for competitive running.
Haas' Santino Ferrucci was seventh and spent much of the morning completing practice pit stops in the VF-16. He was two-tenths quicker than Jolyon Palmer, with the Renault team trialling various suspension setups in a bid to move up the order.
Sergio Sette Camara made his debut with Toro Rosso following his signature to join Red Bull's junior programme. He finished ahead of Manor development driver Jordan King to complete the 2016 cars.
Wehrlein continued tyre development for Pirelli in the 2014 Mercedes W05.
The day was drama free until the checkered flag fell, as Palmer caused a red flag as his engine sent out a puff of blue smoke to bring the session to a close.
Wednesday Test Times – Silverstone:
| # | Driver | Team | Time | Gap | Laps |
| 1 | Kimi Raikkonen | Ferrari | 1:30.665 | 103 | |
| 2 | Esteban Ocon | Mercedes | 1:31.212 | 0.547 | 139 |
| 3 | Pierre Gasly | Red Bull | 1:31.429 | 0.764 | 103 |
| 4 | Nikita Mazepin | Force India | 1:31.561 | 0.896 | 69 |
| 5 | Stoffel Vandoorne | McLaren | 1:31.764 | 1.099 | 114 |
| 6 | Valtteri Bottas | Williams | 1:32.423 | 1.758 | 98 |
| 7 | Santino Ferrucci | Haas | 1:33.141 | 2.476 | 107 |
| 8 | Jolyon Palmer | Renault | 1:33.308 | 2.643 | 98 |
| 9 | Sergio Sette Camara | Toro Rosso | 1:34.040 | 3.375 | 82 |
| 10 | Jordan King | Manor | 1:35.060 | 4.395 | 70 |
| 11 | Pascal Wehrlein | Mercedes* | 1:36.182 | 5.517 | 127 |
