| 16.3.2013 | 12 h Sebring | 01 | #08 | Brabham / Sharp / Cosmo | Extreme Speed Motorsports | 37th |
| 16.3.2013 | 12 h Sebring | 02 | #06 | Lazzaro / Brown / Van Overbeek | Extreme Speed Motorsports | 13th |
| 16.3.2013 | 12 h Sebring | 551 | #02 | Tucker / Franchitti / Briscoe | Level 5 Motorsports | 6th |
| 16.3.2013 | 12 h Sebring | 552 | #03 | Hunter-Reay / Tucker / Pagenaud | Level 5 Motorsports | 7th |
| 13.4.2013 | 3 h Silverstone | 44 | | Dean Stirling | Orex Competition | DNA |
| 14.4.2013 | 6 h Silverstone | 44 | | Popow / Dalziel | Starworks Motorsport | DNA |
| 20.4.2013 | 2 h Long Beach | 01 | #08 | Cosmo / Sharp | Extreme Speed Motorsports | 6th |
| 20.4.2013 | 2 h Long Beach | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 8th |
| 20.4.2013 | 2 h Long Beach | 551 | #02 | Tucker / Briscoe | Level 5 Motorsports | 28th |
| 20.4.2013 | 2 h Long Beach | 552 | #03 | Franchitti / Tucker | Level 5 Motorsports | 30th |
| 11.5.2013 | 4 h Laguna Seca | 01 | #08 | Cosmo / Sharp | Extreme Speed Motorsports | 16th |
| 11.5.2013 | 4 h Laguna Seca | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 34th |
| 11.5.2013 | 4 h Laguna Seca | 551 | #02 | Tucker / Franchitti | Level 5 Motorsports | 3rd |
| 11.5.2013 | 4 h Laguna Seca | 552 | #03 | Briscoe / Tucker | Level 5 Motorsports | 4th |
| 9.6.2013 | Le Mans Test | 33 | #03 | Tucker / Franchitti / Briscoe | Level 5 Motorsports | 25th |
| 9.6.2013 | Le Mans Test | 44 | #02 | Tucker / Franchitti / Briscoe | Level 5 Motorsports | 28th |
| 23.6.2013 | 24 h Le Mans | 33 | #03 | Briscoe / Tucker / Franchitti | Level 5 Motorsports | NC |
| 23.6.2013 | 24 h Le Mans | 44 | | Ryan Dalziel | Starworks Motorsport | DNA |
| 6.7.2013 | 2 h 45 min Lime Rock | 01 | #08 | Sharp / Cosmo | Extreme Speed Motorsports | 4th |
| 6.7.2013 | 2 h 45 min Lime Rock | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 9th |
| 6.7.2013 | 2 h 45 min Lime Rock | 551 | #02 | Tucker / Briscoe | Level 5 Motorsports | 3rd |
| 6.7.2013 | 2 h 45 min Lime Rock | 552 | #03 | Tucker / Franchitti | Level 5 Motorsports | 7th |
| 21.7.2013 | 2 h 45 min Mosport | 01 | #08 | Cosmo / Sharp | Extreme Speed Motorsports | 3rd |
| 21.7.2013 | 2 h 45 min Mosport | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 5th |
| 21.7.2013 | 2 h 45 min Mosport | 551 | #02 | Tucker / Franchitti | Level 5 Motorsports | 2nd |
| 21.7.2013 | 2 h 45 min Mosport | 552 | #03 | Conway / Tucker | Level 5 Motorsports | 4th |
| 11.8.2013 | 2 h 45 min Road America | 01 | #08 | Sharp / Cosmo | Extreme Speed Motorsports | 7th |
| 11.8.2013 | 2 h 45 min Road America | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 31st |
| 11.8.2013 | 2 h 45 min Road America | 551 | #02 | Tucker / Pagenaud | Level 5 Motorsports | 6th |
| 11.8.2013 | 2 h 45 min Road America | 552 | #03 | Gonzalez / Franchitti / Tucker | Level 5 Motorsports | 8th |
| 31.8.2013 | 2 h Baltimore | 01 | #08 | Lazzaro / Sharp | Extreme Speed Motorsports | 4th |
| 31.8.2013 | 2 h Baltimore | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 24th |
| 31.8.2013 | 2 h Baltimore | 551 | #02 | Tucker / Briscoe | Level 5 Motorsports | 27th |
| 31.8.2013 | 2 h Baltimore | 552 | #03 | Cosmo / Tucker / Franchitti | Level 5 Motorsports | 3rd |
| 21.9.2013 | 2 h 45 min Austin | 01 | #08 | Lazzaro / Sharp | Extreme Speed Motorsports | 6th |
| 21.9.2013 | 2 h 45 min Austin | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 5th |
| 21.9.2013 | 2 h 45 min Austin | 551 | #09 | Tucker / Briscoe | Level 5 Motorsports | 3rd |
| 21.9.2013 | 2 h 45 min Austin | 552 | #03 | Cosmo / Franchitti / Tucker | Level 5 Motorsports | 4th |
| 5.10.2013 | 2 h 45 min Virginia | 01 | #08 | Sharp / Lazzaro | Extreme Speed Motorsports | 4th |
| 5.10.2013 | 2 h 45 min Virginia | 02 | #06 | Brown / Van Overbeek | Extreme Speed Motorsports | 32nd |
| 5.10.2013 | 2 h 45 min Virginia | 551 | #09 | Tucker / Briscoe | Level 5 Motorsports | 3rd |
| 5.10.2013 | 2 h 45 min Virginia | 552 | #03 | Franchitti / Cosmo / Johansson | Level 5 Motorsports | 5th |
| 19.10.2013 | Petit Le Mans | 01 | #08 | Sharp / Lazzaro / Brabham | Extreme Speed Motorsports | 3rd |
| 19.10.2013 | Petit Le Mans | 02 | #06 | Brown / Bell / Van Overbeek | Extreme Speed Motorsports | 17th |
| 19.10.2013 | Petit Le Mans | 551 | #09 | Tucker / Briscoe / Franchitti | Level 5 Motorsports | 2nd |
| 19.10.2013 | Petit Le Mans | 552 | #03 | Cosmo / Kane / Dumbreck | Level 5 Motorsports | 4th |
| 17.11.2013 | Sebring November Test | 2 | #06 | Brown / Dalziel / Van Overbeek / Sharp | Extreme Speed Motorsports | 4th |
| 20.11.2013 | Daytona November Test | 2 | #06 | Brown / Dalziel | Extreme Speed Motorsports | 11th |