The 2005 GP2 Series season was the thirty-ninth season of the second-tier of Formula One feeder championship and also first season under the GP2 Series moniker. The season started in Imola, Italy on 23 April, and ended in Sakhir, Bahrain on 30 September. The season was won by the German Nico Rosberg, with the Finn Heikki Kovalainen finishing second.
2005 was the first season of the newly renamed Formula One feeder series, from Formula 3000 to GP2. The inaugural season did not feature reigning F3000 champion Vitantonio Liuzzi, because the Italian was driving for Red Bull Racing in Formula One. The series did feature two former F1 drivers, Italians Gianmaria Bruni and Giorgio Pantano, driving for Coloni and SuperNova respectively.
In the opening race at Imola, there were a number of mechanical problems and with organisers afraid of trouble at the start, the rolling start was used in both races despite the weather being dry. Nicolas Lapierre had taken his inaugural pole position but he was out before the race had started due to mechanical problems. The race was won by his team-mate Heikki Kovalainen.
After the first weekend, it was decided that the points for the fastest lap would only be awarded if the driver was classified. This was due to the event in the Imola sprint race, where Lapierre started with a fuel load with which he wouldn't have been able to finish, set a fastest lap and retired soon after.
At Montmeló, the drivers could finally experience standing starts. F1 refugee Bruni won the feature race and José María López the sprint race. The first four races had been won by four drivers in four teams, highlighting that the field had many competitive drivers. Adam Carroll was the first driver to take a second victory after he won at Monaco, where only one race was held.
At Nürburgring, the sprint race was extended from 80 to 120 kilometres. This coincided with F1 dropping its second qualifying session on Sunday morning. The sprint race turned to be one of the most exciting of the season, with Monegasque Clivio Piccione winning.
Heikki Kovalainen was the top driver early in the season, winning three of the first five feature races. However, the season took a turnaround at Magny-Cours, where ART Grand Prix started going strong. Tactical errors caused them to lose the feature race, but Nico Rosberg gave them their first win at the sprint. Rosberg went on to win the next two feature races, while Olivier Pla won both sprints having started from pole position in both of them.
At the qualifying of the Hungaroring race, ART cars were disqualified for illegal position of their steering rack. They were sent to back of the grid but it didn't stop them taking points finishes in the feature and 1-2 in the sprint race, where Alexandre Prémat won his first race. Neel Jani joined the winners' list in the feature race.
Prémat also won the next race at Istanbul, while championship leading duo Kovalainen and Rosberg finished outside the points. The sprint race started in wet conditions but dried out, so tyre changes were necessary. Kovalainen did that move perfectly and won the race having started 10th. Rosberg jumped from 17th to 3rd.
Kovalainen and Jani won races at Monza but Rosberg took the most points with two second places and two fastest laps. Nelson Piquet Jr. then won the feature race at Spa-Francorchamps while Rosberg took the championship lead from Kovalainen who spun off on the last lap while battling for eighth place and pole for Sunday's race. Carroll led the sprint race from the start but following accidents involving Ernesto Viso, Hiroki Yoshimoto and Jani the race was stopped early and only half points were awarded. Viso still ended in 3rd position thanks to countback rule.
The championship was decided in Bahrain which held the only race not supporting F1. Rosberg led Kovalainen by three points and increased his lead by taking pole position. Rosberg also won the race and clinched the title as Kovalainen was 3rd. Rosberg then also won the sprint race, becoming the first driver in the series to win both races during an event.
All of the teams used the Dallara GP2/05 chassis with Renault-badged 4.0 litre (244 cu in) naturally-aspirated Mecachrome V8 engines in 2005 in order to keep the field fair.
As this was the inaugural season in the series, car numbers were distributed by a pre-season session held at Circuit Paul Ricard on 6 April. The fastest driver got number 1, his team-mate number 2, next best driver number 3 etc.[1]
| Team | Driver name | Rounds | |
|---|---|---|---|
 iSport International | 1 |  Scott Speed | All |
| 2 |  Can Artam | All | |
| Hitech Piquet Sports | 3 |  Nelson Piquet Jr. | All |
| 4 | Alexandre Negrão | All | |
 BCN Competición | 5 |  Ernesto Viso | All |
| 6 |  Hiroki Yoshimoto | All | |
| Super Nova International | 7 |  Giorgio Pantano | All |
| 8 | Adam Carroll | All | |
 ART Grand Prix | 9 |  Nico Rosberg | All |
| 10 | Alexandre Prémat | All | |
| DPR | 11 | Olivier Pla | All |
| 12 | Ryan Sharp | 1–7 | |
| Giorgio Mondini | 8–12 | ||
| DAMS | 14 | José María López | All |
| 15 | Fairuz Fauzy | All | |
| Coloni Motorsport | 16 |  Mathias Lauda | All |
| 17 | Gianmaria Bruni | 1–9 | |
 Toni Vilander | 10–11 | ||
| nowrap | Ferdinando Monfardini | 12 | |
| Racing Engineering | 18 |  Neel Jani | All |
| 19 | Borja García | All | |
| Campos Racing | 20 | Juan Cruz Álvarez | All |
| 21 | Sergio Hernández | All | |
| Arden International | 22 | Heikki Kovalainen | All |
| 23 | Nicolas Lapierre | All | |
| Durango | 24 |  Clivio Piccione | All |
| 25 | Ferdinando Monfardini | 1–10 | |
| Gianmaria Bruni | 11–12 |
There were 23 races in the 2005 GP2 Series championship at 12 different circuits. Eleven race weekends had one race on Saturday and another on Sunday, the exception being the race at Circuit de Monaco where there was only one race on the weekend. The season began on 23 April 2005 and concluded on 25 September 2005.
The calendar was as follows:
| Round | Location | Circuit | Date | Supporting | |
|---|---|---|---|---|---|
| 1 | Imola, Italy | Autodromo Enzo e Dino Ferrari | 23 April | San Marino Grand Prix | |
| 24 April | |||||
| 2 | F | Montmeló, Spain | Circuit de Catalunya | 7 May | Spanish Grand Prix |
| S | 8 May | ||||
| 3 | F | Monaco | Circuit de Monaco | 21 May | Monaco Grand Prix |
| 4 | F | Nürburg, Germany | Nürburgring | 28 May | European Grand Prix |
| S | 29 May | ||||
| 5 | F | Magny-Cours, France | Circuit de Nevers Magny-Cours | 2 July | French Grand Prix |
| S | 3 July | ||||
| 6 | F | Silverstone, UK | Silverstone Circuit | 9 July | British Grand Prix |
| S | 10 July | ||||
| 7 | F | Hockenheim, Germany | Hockenheimring | 23 July | German Grand Prix |
| S | 24 July | ||||
| 8 | F |  Mogyoród, Hungary | Hungaroring | 30 July | Hungarian Grand Prix |
| S | 31 July | ||||
| 9 | F | Istanbul, Turkey | Istanbul Racing Circuit | 20 August | Turkish Grand Prix |
| S | 21 August | ||||
| 10 | F | Monza, Italy | Autodromo Nazionale Monza | 3 September | Italian Grand Prix |
| S | 4 September | ||||
| 11 | F |  Stavelot, Belgium | Circuit de Spa-Francorchamps | 10 September | Belgian Grand Prix |
| S | 11 September | ||||
| 12 | F |  Sakhir, Bahrain | Bahrain International Circuit | 29 September | Stand-alone event |
| S | 30 September | ||||
| Position | 1st | 2nd | 3rd | 4th | 5th | 6th | 7th | 8th | Pole | FL | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Points | 10 | 8 | 6 | 5 | 4 | 3 | 2 | 1 | 2 | 2 |
| Position | 1st | 2nd | 3rd | 4th | 5th | 6th | FL | |
|---|---|---|---|---|---|---|---|---|
| Points | 6 | 5 | 4 | 3 | 2 | 1 | 2 |
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Notes:
| Pos | Team | Car No. | IMO | CAT | MON | NÜR | MAG | SIL | HOC | HUN | IST | MNZ | SPA‡ | BHR | Points | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | ART Grand Prix | 9 | 8 | Ret | 9 | 4 | 3 | 3 | 4 | 7 | 1 | 1 | 4 | 1 | 4 | 5 | 2 | 17 | 3 | 2 | 2 | 3 | 5 | 1 | 1 | 187 | |
| 10 | 7 | 2 | 10 | Ret | Ret | 4 | Ret | 9 | Ret | 3 | 5 | 2 | 9 | 4 | 1 | 1 | 14 | Ret | 18 | Ret | 12 | 2 | 3 | ||||
| 2 | Arden International | 22 | 1 | 3 | 3 | Ret | 5 | 1 | Ret | 1 | 3 | 2 | 3 | 5 | 6 | 2 | 5 | 10 | 1 | 1 | 5 | 15† | 9 | 3 | Ret | 126 | |
| 23 | DNS | Ret | 11 | 9 | Ret | 12 | Ret | 3 | 5 | 10 | Ret | 9 | 7 | 12 | 6 | Ret | 13 | 4 | Ret | Ret | 23† | 6 | 20 | ||||
| 3 | Super Nova International | 7 | 13† | Ret | 13 | 14 | Ret | 2 | 7 | 10 | 7 | 12 | 7 | 6 | 2 | 3 | 3 | 2 | 8 | 6 | 3 | NC | 11 | 5 | 5 | 102 | |
| 8 | 5 | 1 | 7 | 6 | 1 | Ret | 2 | 4 | 6 | 21† | 8 | Ret | 11 | 9 | 9 | 7 | 2 | 5 | 6 | 8 | 1 | 9 | 8 | ||||
| 4 | iSport International | 1 | 3 | Ret | 2 | 3 | 4 | 16 | 12 | 15 | 18 | 4 | 2 | 4 | 3 | Ret | 19 | 5 | 4 | Ret | 15 | 4 | 4 | Ret | 19 | 69.5 | |
| 2 | 16† | Ret | Ret | Ret | 7 | 17 | Ret | 17 | 16 | 18 | 14 | Ret | 20 | 14 | 12 | 11 | 16 | 9 | 9 | Ret | 22† | 17 | 16 | ||||
| 5 | Racing Engineering | 18 | 6 | 15 | 4 | 5 | Ret | 6 | 13† | 5 | 4 | 5 | 6 | Ret | 22 | 1 | 4 | Ret | Ret | 7 | 1 | 16 | 18 | 16 | 13 | 65.5 | |
| 19 | Ret | 10 | Ret | 10 | 10† | Ret | EX | Ret | 12 | 17 | 9 | 7 | 5 | 11 | Ret | 3 | 5 | Ret | 10 | 6 | 2 | 19† | 17 | ||||
| 6 | Hitech Piquet Sports | 3 | 14† | 6 | 5 | 2 | 11† | 5 | 3 | Ret | DSQ | DNS | Ret | 3 | 8 | 15† | 10 | 4 | 6 | 3 | Ret | 1 | 14 | Ret | 15 | 50 | |
| 4 | Ret | 13 | 8 | 15 | 12† | Ret | Ret | Ret | 13 | 19 | 16† | Ret | 18 | 8 | 15 | 12 | 19 | Ret | 13 | 7 | 7 | 12 | 9 | ||||
| 7 | DAMS | 14 | 2 | 11 | 6 | 1 | Ret | 13 | 14 | 2 | Ret | 9 | DNS | 13 | 10 | Ret | Ret | 6 | 7 | Ret | Ret | 10 | 8 | 4 | 4 | 36 | |
| 15 | 17† | 12 | 12 | 7 | Ret | 14 | 10 | 14 | 10 | Ret | DNS | Ret | 16 | Ret | 13 | Ret | 15 | 14 | 11 | 13 | 15 | 11 | 10 | ||||
| 8 | Coloni Motorsport | 16 | 12 | Ret | Ret | 13 | 6 | 10 | Ret | 16 | 15 | 20 | 15 | 14 | 21 | Ret | 14 | 16 | 18 | 13 | 12 | 9 | 24† | 14 | 21 | 36 | |
| 17 | 4 | 4 | 1 | Ret | 2 | 8 | Ret | 18 | 11 | 7 | 11 | NC | 14 | 10 | 8 | Ret | 9 | 15 | 8 | 14 | 13 | Ret | 11 | ||||
| 9 | BCN Competición | 5 | 10 | DNS | Ret | Ret | DSQ | Ret | 11 | 11 | 8 | 15 | 13 | DSQ | 12 | 6 | Ret | 14 | 12 | Ret | Ret | 2 | 3 | 8 | 2 | 35 | |
| 6 | Ret | 9 | Ret | 17 | DNS | 11 | DNS | 6 | 2 | 13 | DNS | 12 | Ret | 13 | 17 | 8 | 10 | 10 | 16 | Ret | 17 | 7 | 6 | ||||
| 10 | DPR | 11 | 9 | 5 | Ret | Ret | 9 | Ret | 8 | Ret | 9 | 8 | 1 | 8 | 1 | 7 | Ret | 9 | 17 | Ret | Ret | 11 | 10 | Ret | DNS | 22 | |
| 12 | Ret | 14 | Ret | 16 | Ret | 9 | 9 | 19 | Ret | Ret | NC | 11 | 13 | Ret | Ret | 13 | Ret | Ret | Ret | Ret | 21† | 18 | 22 | ||||
| 11 | Durango | 24 | 15 | Ret | Ret | 8 | Ret | 7 | 1 | 8 | DSQ | 6 | Ret | Ret | 17 | Ret | 16 | Ret | 11 | 11 | 14 | 12 | 19 | 13 | 7 | 21 | |
| 25 | Ret | DNS | Ret | 11 | DNS | Ret | 6 | 12 | 17† | 14 | 10 | Ret | 15 | Ret | 11 | Ret | Ret | 8 | 4 | Ret | 16 | Ret | 14 | ||||
| 12 | Campos Racing | 20 | Ret | 7 | Ret | 12 | Ret | 18† | 15 | Ret | DSQ | 11 | Ret | 10 | NC | Ret | 7 | 15 | Ret | 12 | 17† | 5 | 6 | 10 | 12 | 7.5 | |
| 21 | 11 | 8 | Ret | 18† | 8 | 15 | 5 | 13 | 14 | 16 | 12 | Ret | 19 | Ret | 18† | Ret | 20† | Ret | 7 | Ret | 20† | 15 | 18 | ||||
| Pos | Team | Car No. | IMO | CAT | MON | NÜR | MAG | SIL | HOC | HUN | IST | MNZ | SPA | BHR | Points | ||||||||||||
