HPD ARX-03 - short-lived championship winning prototype
The HPD ARX-03 is a prototype race car developed by an American company Honda Performance Department (HPD) in 2012, according to Le Mans Prototype (LMP) rules, to compete in the American Le Mans Series and FIA World Endurance Championship.
Two different versions of the car, the ARX-03a and ARX-03b, were dominant entries in the 2012 and 2013 American Le Mans Series, winning all titles in P1 and P2 categories two years in a row. ARX-03b was also successful in the 2012 FIA WEC season, winning the world championship and taking the LMP2 class victory at Le Mans 24h.
Two-in-one ARX-03 succeeded ARX-01 and ARX-02
After having an Acura ARX-01 in the LMP2 class and Acura ARX-02 in the LMP1 class between 2007 and 2011, HPD decided to develop a chassis which could utilize two different engines and compete in two classes at the same time. For the 2012 racing season, HPD also decided to focus on being a chassis and engine provider.
V8 engine for LMP1 class, V6 engine for LMP2 class
The HPD ARX-03 is made with carbon fiber monocoque chassis, featuring HPD-Hewland six-speed sequential gearbox for both versions of the car. The ARX-03a LMP1 prototype was using the 3.4L naturally aspirated Honda V8 engine while ARX-03b LMP2 prototype was using the 2.8L turbocharged Honda V6 engine.
Two teams with ARX-03 cars in the 2012 ALMS season
The first buyers were Muscle Milk Pickett Racing, which purchased the ARX-03a, and Level 5 Motorsports, which purchased two ARX-03b cars. Both teams achieved a great success, winning LMP1 and LMP2 championship titles in the 2012 American Le Mans Series.
In the season-opening Sebring 12 hours, HPD ARX-03b scored a 1-2 victory in the LMP2/P2 class, with Starworks Motorsport’s Ryan Dalziel, Enzo Potolicchio and Stephane Sarrazin as the winners and Level 5 Motorsports’ Scott Tucker, Joao Barbosa and Christophe Bouchut drivers finished in second place. Level 5 Motorsports’ crew was eligible to score ALMS points.
Championship titles in both ALMS prototype classes
In the ALMS P1 class, Muscle Milk Pickett Racing fought against Dyson Racing’s Lola B12/60-Mazda. At the end, with six wins on its account and five points more than rivals, Muscle Milk Pickett Racing took teams’ championship while Klaus Graf and Lucas Luhr became ALMS drivers’ champions.
2012 Le Mans 24h win for Starworks Motorsport
In the 2012 FIA World Endurance Championship, Strakka Racing and JRM Racing campaigned a single ARX-03a each, joined by a single-car ARX-03b entry by Starworks Motorsport in the LMP2 class. Starworks Motorsports scored three FIA WEC LMP2 class wins (Sebring, Le Mans, Sao Paulo), winning the championship title in a revived World Championship.
Enzo Potolicchio and Ryan Dalziel participated in all three wins, with Stephane Sarrazin as a co-driver two times, while Tom Kimber-Smith was a co-driver in the #44 car at Le Mans 24h. Starworks’ ARX-03b scored an LMP2 Le Mans victory ahead of two Oreca 03 prototypes.
In the FIA WEC LMP1 class, Strakka Racing and JRM finished second and third in the LMP1 Privateer Trophy behind the Swiss Rebellion Racing. Strakka Racing scored only one win with ARX-03a, winning the 6 Hours of Bahrain.
Updated ARX-03c has won 2013 ALMS title
In the 2013 ALMS season, Muscle Milk Pickett Racing continued to run HPD ARX-03a, moving to the updated ARX-03c car from the fourth round. The team claimed eight wins in ten races, so Lucas Luhr and Klaus Graf defended their championship titles.
In the P2 field of the American Le Mans Series, only two teams participated, both with HPD ARX-03b cars: Extreme Speed Motorsports and Level 5 Motorsports. Level 5 won a duel, scoring eight wins against two wins of the ESM.
Strakka Racing was the last ARX-03 entry in the FIA WEC
In the 2013 FIA WEC season, only Strakka Racing was using an HPD ARX-03c car in the first three rounds of the championship, withdrawing after that from the championship. In those three races, Strakka’s only rival in the FIA Endurance Trophy for Private LMP1 teams was Rebellion Racing. Strakka’s Nick Leventis, Jonny Kane and Danny Watts finished sixth overall at Le Mans and were the best among privateers.
Last win for ARX-03b at Laguna Seca
In 2014, ALMS and Grand-Am Rolex Sports Car Serie merged into IMSA United Sports Car Championship, with Daytona Prototypes and LMP2 cars as a top class. Extreme Speed Motorsports was the only team to run HPD ARX-03b, with #1 and #2 cars in the field. The #2 car was victorious at Laguna Seca, with Ed Brown and Johannes van Overbeek as drivers. They finished 8th in final standings of the championship and the team took the seventh place.
Disappointing 2015 season was the end of a story
For the 2015 IMSA season, Extreme Speed Motorsports ordered a new closed-cockpit HPD ARX-04b. After a disappointing start of the season at Daytona 24h, where both cars retired, the team returned to the older ARX-03b car in the next race. The performance at Sebring wasn’t much better, so ESM withdrew from the championship to concentrate on the FIA WEC campaign. In the World Championship, Extreme Speed Motorsports was running ARX-03b only at the season-opening 6 hours of Silverstone, switching to Ligier-Nissan prototype after that.
HPD ARX-03 technical specifications
|Chassis||Carbon fiber monocoque|
|Engine||ARX-03a: 3.4L V8 naturally aspirated; ARX-03b: 2.8L V6 turbocharged|
|Power/torque||ARX-03a: 535 hp; ARX-03b: 450 hp|
|Gearbox||HPD-Hewland 6-speed sequential|
|Suspension (front/rear)||Double wishbone with adjustable toe, camber, ride heights. Four-way damber units with separate coil springs, pushrods with anti-roll bars|
|Brakes||Ventilated carbon-ceramic discs, 6-pot caliper|
Photos: hpd.honda.com, racecar-engineering.com, supercars.net, motorsport.com,