2003 American Le Mans Series
The 2003 American Le Mans Series season was the fifth season for the IMSA American Le Mans Series, and the 33rd overall season of the IMSA GT Championship. It was a series for Le Mans Prototypes and Grand Touring race cars divided into 4 classes: LMP900, LMP675, GTS, and GT. It began March 15, 2003 and ended October 18, 2003 after 9 races.
Dyson Racing's overall win at Sonoma Raceway was the first time in ALMS history that the overall win was captured by a vehicle not from the LMP900 class.
Schedule
Little was changed between the 2002 and 2003 schedules; the Grand Prix of Washington, D. C. and Mid-Ohio Sports Car Course did not return, but both were instead replaced by the return of the Grand Prix of Atlanta at Road Atlanta. The Grand Prix of Mexico was originally scheduled for April 6 at the Autodromo Hermanos Rodriguez but was canceled| Rnd | Race | Circuit | Date |
| 1 | Mobil 1 12 Hours of Sebring | Sebring International Raceway | March 15 |
| C | Grand Prix of Mexico | Autodromo Hermanos Rodriguez | April 6 |
| 2 | Chevy Grand Prix of Atlanta | Road Atlanta | June 29 |
| 3 | Infineon Grand Prix of Sonoma | Sonoma Raceway | July 27 |
| 4 | Le Grand Prix de Trois-Rivières | Circuit Trois-Rivières | August 3 |
| 5 | Toronto Grand Prix of Mosport | Mosport | August 17 |
| 6 | Road America 500 | Road America | August 24 |
| 7 | Fry's Electronics Sports Car Championships | Mazda Raceway Laguna Seca | September 7 |
| 8 | Grand Prix Americas | Miami street circuit | September 27 |
| 9 | Petit Le Mans | Road Atlanta | October 18 |
Season results
Overall winner in bold.| Rnd | Circuit | LMP900 Winning Team | LMP675 Winning Team | GTS Winning Team | GT Winning Team | Results |
| Rnd | Circuit | LMP900 Winning Drivers | LMP675 Winning Drivers | GTS Winning Drivers | GT Winning Drivers | Results |
| 1 | Sebring |  #1 Infineon Team Joest |  #20 Dyson Racing | #3 Corvette Racing | #23 Alex Job Racing | Results |
| 1 | Sebring | Frank Biela Marco Werner Philipp Peter |  Didier de Radiguès Chad Block Chris Dyson |  Ron Fellows Johnny O'Connell Franck Fréon | Sascha Maassen Lucas Luhr | Results |
| 2 | Road Atlanta | #38 ADT Champion Racing | #37 Intersport Racing | #4 Corvette Racing | #24 Alex Job Racing | Results |
| 2 | Road Atlanta |  JJ Lehto Johnny Herbert | Duncan Dayton Jon Field | Kelly Collins Oliver Gavin | Jörg Bergmeister Timo Bernhard | Results |
| 3 | Sonoma | #1 Infineon Team Joest | #16 Dyson Racing | #3 Corvette Racing | #23 Alex Job Racing | Results |
| 3 | Sonoma | Frank Biela Marco Werner | Butch Leitzinger James Weaver | Ron Fellows Johnny O'Connell | Sascha Maassen Lucas Luhr | Results |
| 4 | Trois-Rivières | #1 Infineon Team Joest | #37 Intersport Racing | #4 Corvette Racing | #23 Alex Job Racing | Results |
| 4 | Trois-Rivières | Frank Biela Marco Werner | Jon Field Duncan Dayton | Kelly Collins Oliver Gavin | Sascha Maassen Lucas Luhr | Results |
| 5 | Mosport | #1 Infineon Team Joest | #20 Dyson Racing | #3 Corvette Racing | #24 Alex Job Racing | Results |
| 5 | Mosport | Frank Biela Marco Werner | Andy Wallace Chris Dyson | Ron Fellows Johnny O'Connell | Jörg Bergmeister Timo Bernhard | Results |
| 6 | Road America | #38 ADT Champion Racing | #20 Dyson Racing | #80 Prodrive | #31 Petersen/White Lightning | Results |
| 6 | Road America | JJ Lehto Johnny Herbert | Andy Wallace Chris Dyson |  Jan Magnussen David Brabham | Craig Stanton Johnny Mowlem | Results |
| 7 | Laguna Seca | #1 Infineon Team Joest | #16 Dyson Racing | #80 Prodrive | #23 Alex Job Racing | Results |
| 7 | Laguna Seca | Frank Biela Marco Werner | Butch Leitzinger James Weaver | Jan Magnussen David Brabham | Sascha Maassen Lucas Luhr | Results |
| 8 | Miami | #38 ADT Champion Racing | #20 Dyson Racing | #80 Prodrive | #23 Alex Job Racing | Results |
| 8 | Miami | JJ Lehto Johnny Herbert | Andy Wallace Chris Dyson | Darren Turner David Brabham | Sascha Maassen Lucas Luhr | Results |
| 9 | Road Atlanta | #38 ADT Champion Racing | #37 Intersport Racing | #88 Prodrive | #24 Alex Job Racing | Results |
| 9 | Road Atlanta | JJ Lehto Johnny Herbert | Jon Field Clint Field Larry Connor |  Alain Menu Tomáš Enge Peter Kox | Jörg Bergmeister Timo Bernhard Romain Dumas | Results |
Teams Championship
Points are awarded to the top 10 finishers in the following order:- 20-16-13-10-8-6-4-3-2-1
- 26-22-19-16-14-12-10-9-8-7
LMP900 Standings
LMP675 Standings
GTS Standings
| Pos | Team | Chassis | Engine | Rd 1 | Rd 2 | Rd 3 | Rd 4 | Rd 5 | Rd 6 | Rd 7 | Rd 8 | Rd 9 | Total |
| 1 | Corvette Racing | Chevrolet Corvette C5-R | Chevrolet 7.0L V8 | 26 | 20 | 20 | 20 | 20 | 16 | 16 | 10 | 19 | 167 |
| 2 | Prodrive | Ferrari 550-GTS Maranello | Ferrari 6.0L V12 | 22 | 16 | 13 | 10 | 16 | 20 | 20 | 20 | 26 | 163 |
| 3 |  Team Olive Garden | Ferrari 550 Maranello | Ferrari 6.0L V12 | 8 | 8 | 13 | 10 | 10 | 10 | 13 | 72 | ||
| 4 | Carsport America | Dodge Viper GTS-R Pagani Zonda GR | Dodge 8.0L V10 Mercedes-AMG 6.3L V12 | 16 | 6 | 8 | 4 | 8 | 42 | ||||
| 5 | Konrad Motorsport | Saleen S7-R | Ford 7.0L V8 | 6 | 6 |