Honda Performance Development introduced three variants of the ARX-03 for the 2012 season. The ARX-03a uses a Honda V8 engine and targets the LMP1 category, while the ARX-03b pairs a turbocharged V6 with LMP2 regulations. The ARX-03c is an updated version of the package that arrived mid-2013. Teams from both North America and Europe campaigned the car, including Muscle Milk Pickett Racing and Level 5 Motorsports in the American Le Mans Series, and Strakka Racing, JRM Racing, and Starworks Motorsport in the FIA World Endurance Championship.
The HPD ARX-03 made its racing debut at the 2012 12 Hours of Sebring, which served as the opening round of both the American Le Mans Series and the newly formed FIA World Endurance Championship. Muscle Milk Pickett Racing ran an ARX-03a in LMP1, while Level 5 Motorsports entered two ARX-03bs in LMP2.
After a fueling problem at Sebring, the Muscle Milk team rebounded by winning the next five races in succession, adding another victory at Virginia International Raceway. At the season finale at Petit Le Mans, driver Lucas Luhr was struck by a GTC class Porsche and required repairs mid-race, but the team completed enough of the event to score championship points. Muscle Milk Pickett Racing ultimately won both the LMP1 drivers and team championships, edging main rivals Dyson Racing by just five points.
Level 5 Motorsports responded with equal dominance in LMP2, taking first in class at the 12 Hours of Sebring and winning seven of the next nine rounds. Their only defeats came at Mosport and Road America, where rivals Conquest Endurance prevailed. Level 5 secured both the LMP2 Teams Championship and the Drivers Championship.
In the FIA World Endurance Championship, Starworks Motorsport claimed three class victories with the ARX-03b, including the season-opening Sebring round and the 24 Hours of Le Mans, and won the LMP2 trophy. Strakka Racing and JRM each campaigned ARX-03as in LMP1, finishing second and third respectively in the LMP1 Privateer Trophy behind Rebellion Racing, with Strakka claiming one class victory over the course of the season.
Muscle Milk Pickett Racing began the 2013 American Le Mans Series season with the ARX-03a before transitioning to the updated ARX-03c from the fourth round onward. Despite losing at Sebring to Rebellion Racing and Audi Sport Team Joest, and suffering an overheating failure at the season-ending Petit Le Mans, the team claimed eight wins from ten races and successfully defended both the LMP1 Teams and Drivers Championships.
In LMP2, Extreme Speed Motorsports joined Level 5 Motorsports with the ex-Starworks ARX-03b and a new chassis. Level 5 won every round except Long Beach, where Extreme Speed prevailed, and secured another sweep of the LMP2 Teams and Drivers Championships.
Strakka Racing was the sole HPD entrant in the 2013 FIA World Endurance Championship season, competing in the first three rounds before retiring the car at Silverstone due to damage. Despite the abbreviated campaign, the team finished second in the privateer standings at Spa-Francorchamps and first in class at Le Mans ahead of Rebellion Racing.
The ARX-03 program demonstrated Honda Performance Development's ability to produce a competitive prototype across multiple specifications and regulatory categories simultaneously. The car delivered championship titles in its debut season across both major North American and international endurance series, validating Honda's approach to privateer prototype support through a unified platform available to multiple teams.