Ferrari ended the pre-season test at Jerez on a positive note as Fernando Alonso set the fastest time of the day, and the second best by a 2012 car across all four days at the Spanish track.
The Scuderia had struggled to get on top of the radical F2012 during the opening three days but, with the former world champion at the helm, the Italian team rose to the top of the timesheets early on in day four and was never displaced.
Alonso ended with a best of one minute 18.877 seconds, set at the start of a six-lap run which also included laps in the 1:19 and 1:20.
Jean-Eric Vergne hung on to second despite a late rally from Sebastian Vettel in the RB8, which had been beset by electrical issues in the morning.
Vergne finished his second day for Toro Rosso with a 1:19.597, nine thousandths quicker than Vettel's benchmark, set in the afternoon when conditions were not at their prime.
Lewis Hamilton finished fourth, just 34 thousandths of a second down the road in McLaren's MP4-27.
Romain Grosjean did not get down to his day three benchmark, but did enough to end the day in fifth with a 1:19.729.
Friday's Test times:
1. Alonso Ferrari 1:18.877 39
2. Vergne Toro Rosso 1:19.597 +0.720 80
3. Vettel Red Bull 1:19.606 +0.729 50
4. Hamilton McLaren 1:19.640 +0.763 86
5. Grosjean Lotus 1:19.729 +0.852 95
6. Kobayashi Sauber 1:19.834 +0.957 76
7. Hulkenberg Force India 1:19.977 +1.100 90
8. Senna Williams 1:20.132 +1.255 125
9. Trulli Caterham 1:22.198 +3.321 117