Lewis Williamson set the pace on the final day of GP3 Series at Estoril on Friday.

Driving for Bamboo Engineering, which only announced its series entry this week, the 23-year-old Briton went fastest in a time of 1m27.675s, almost a second slower than Carlos Sainz Jr.'s mark from the opening day.

A short spell of rain during the afternoon looked set to leave Toyota Racing Series Nick Cassidy, testing for Manor, as the pacesetter. But after the rain stopped the track dried out enough to allow Williamson to jump to the head of the order late in the day. His time was 0.088sec faster than MW Arden driver Daniil Kvyat's.

Robert Visoiu made it two Arden cars in the top three while British Formula 3 champion Jack Harvey was next up for ART. Briton Dino Zamparelli (Manor) and Italian David Fumanelli (Trident) were next up.

As was the case on Thursday, the day began with a wet track, although unlike 24 hours earlier, the rain continued to fall for much of the morning, leaving lap times around 15s off the marks that would be achieved later. Kevin Korjus, driving for another new series entrant, Koiranen GP, was the fastest driver in the wet conditions, almost 0.3sec faster than MW Arden man Sainz.

Harvey, Fumanelli, Patrick Kujala, Patric Niederhauser, Alex Fontana and Jimmy Eriksson all caused red flags during the day thanks to a combination of spins and mechanical problems.

Pos  Driver                  Team        Time     Laps
 1.  Lewis Williamson        Bamboo      1m27.675s  44
 2.  Daniil Kvyat            MW Arden    1m27.763s  46
 3.  Robert Visoiu           MW Arden    1m27.848s  66
 4.  Jack Harvey             ART         1m28.080s  60
 5.  Dino Zamparelli         Manor       1m28.139s  63
 6.  David Fumanelli         Trident     1m28.159s  52
 7.  Alex Fontana            Jenzer      1m28.179s  54 
 8.  Patric Niederhauser     Jenzer      1m28.212s  51 
 9.  Facu Regalia            ART         1m28.322s  60 
10.  Kevin Korjus            Koiranen    1m28.372s  53 
11.  Giovanni Venturini      Trident     1m28.385s  59 
12.  Emanuele Zonzini        Trident     1m28.459s  57
13.  Carlos Sainz Jr         MW Arden    1m28.485s  52
14.  Nick Cassidy            Manor       1m28.522s  74
15.  Conor Daly              ART         1m28.923s  63
16.  Aaro Vainio             Koiranen    1m29.044s  74
17.  Ethan Ringel            Bamboo      1m29.076s  42
18.  Nick Yelloly            Carlin      1m29.104s  56
19.  Patrick Kujala          Koiranen    1m29.335s  41
20.  Luis Sa Silva           Carlin      1m29.341s  75
21.  Vicky Piria             Manor       1m29.461s  54
22.  Josh Webster            Status      1m29.648s  52
23.  Eric Lichtenstein       Carlin      1m29.823s  69
24.  Samin Gomez             Jenzer      1m30.177s  77
25.  Roberto La Rocca        Bamboo      1m30.399s  29
26.  Melville McKee          Status      1m31.780s  37
27.  Jimmy Eriksson          Status      1m32.761s  38