Make no mistake about it: Honda is big in racing. It was the first Japanese automaker to enter Formula One, remains the most successful and is set to return as an engine supplier next season. It's powered more IndyCar race winners and champions than any other manufacturer, hands down. Honda has won races and titles in Super GT, WTCC, even motorcycle racing. Just about everything this side of NASCAR, really. And that includes endurance sports car racing.

In fact Honda Performance Development prototypes claimed over 70 victories and numerous titles in the American Le Mans Series, and took the first LMP2 title in the FIA World Endurance Championship. And with sportscar racing in the US now grouped together into the United SportsCar Championship, Honda is back with a new chassis design.

Called the ARX-04b, it's Honda's first closed-cockpit LMP2. Like previous LMP2 and IndyCar projects, it's a joint development between HPD and Wirth Research, and packs Honda's HR28TT engine – a 2.8-liter twin-turbo V6 based on (and using many of the same components as) the J35 engine you'd find in a contemporary Acura. Designed to exceed the latest safety regulations, the ARX-04b features low-drag bodywork, quick-change front and rear panels, the same locking fuel filler system that Honda pioneered for Indy, top-exit exhaust to meet noise regulations, a 75-liter fuel tank and a gearbox that can easily be optimized for individual circuits.

Honda will sell the new ARX-04b to privateer teams to field in series like the United SportsCar Championship, European Le Mans Series, Asian Le Mans Series and the World Endurance Championship, starting next season.
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Honda Performance Development ARX-04b LMP2 Coupe unveiled
04/09/2014 - SANTA CLARITA, Calif.

- First closed-top prototype from HPD
- Eligible for IMSA, WEC, ELMS and Asian Le Mans Series competition
- New LMP2 design to debut in 2015

Honda Performance Development will offer customer teams around the world the very latest in LMP2 closed-cockpit sports car technology next year, with the unveiling of its new HPD ARX-04b LMP2 Coupe.

The new design is a result of the continuing teamwork between California-based HPD and England's Wirth Research. This technical pairing has already proved to be a winning combination, with success in INDYCAR, the American Le Mans Series and the FIA World Endurance Championship, including LMP2 and LMP1 Privateer class victories at the 24 Hours of Le Mans.

The ARX-04b sports car is fully compliant with the new ACO LMP2 regulations, and exceeds the latest safety standards of the new enclosed-cockpit configuration. The proven 2.8-liter twin-turbo, direct injection, production-based Honda HR28TT V6 powerplant now includes a regulation compliant drive-by-wire throttle system and fresh air valve system, eliminating turbo lag and providing improved reliability and performance.

"We are very excited for our new HPD ARX-04b LMP2 Coupe to see the light of day, combining all of our successes in international sportscar racing with the very latest regulations for closed-cockpit prototypes," said Steve Eriksen, HPD vice president and COO. "Our production-based Honda HR28TT engine has powered all of our LMP2 sportscars since the ACO regulations set the new cost-capped direction in 2011, and since its introduction the 2.8-litre twin-turbo V6 powerplant has achieved some truly great successes around the world – including multiple engine manufacturer championships, victory at the Sebring 12 Hours and the 24 Hour of Le Mans, as well as powering the first LMP2 FIA World Endurance Champion. We are confident that our latest iteration of the HR28TT engine and its associated systems will satisfy even the most discriminating drivers and power the new HPD ARX-04b LMP2 Coupe to even greater successes around the world."

Additional features of the ARX-04b LMP2 Coupe include:
- Energy-efficient technology with low drag and high fuel efficiency.
- A cost-capped chassis, fully compliant with ACO and IMSA regulations and designed to compete and win the toughest endurance races in the world.
- "Quick Change" front and rear bodywork.
- Innovative Honda refueling safety interlock system designed to reduce the potential for pit fires resulting from leaving the pit box with fuel hoses inserted (applied to all IndyCars since 2011)
- Engine installation includes a proven turbo mounting system and top exit exhaust, meeting all ACO and IMSA noise regulations.
- Gearbox changes which can be made to cover the complete range of circuits.
- A 75-litre total capacity fuel cell, and lightweight, durable bodywork.

The ARX-04b will continue the HR28TT powerplant, developed by HPD from the production Honda "J35" series of V6 engines currently found in the Acura MDX and RLX in North America, in addition to the upcoming 2015 Acura TLX. The racing engine continues to use more than 400 production engine parts, including the engine block and heads, crankshaft, direct-injection fuel system, valve train components, drive-by-wire hardware and even the stock Honda oil filter.

As part of their after-sales support services, HPD and Wirth will provide teams with technical assistance and bulletins, as well as additional options available for purchase. Additional bespoke options include driver-in-the-loop simulator sessions, data-logging, race and performance engineering, and MuRiTyre and Apotheca software.

"Wirth Research is proud of its history of consistently creating championship-winning prototype sports cars with and on behalf of Honda Performance Development (HPD). Using our pioneering CFD design techniques, we have created the all-new HPD ARX-04b LMP2 Coupe," said Wirth Research President Nick Wirth. "Not only is it a stunning-looking race car, we are confident that our revolutionary all-digital design approach will ensure that HPD's 2015 LMP2 Coupe customers will benefit from fielding the most aero-efficient, balanced and competitive LMP2 car on the 2015 grid."

Wirth Research has been at the forefront of Computational Fluid Dynamics (CFD) in high-level motorsports for almost a decade, and has played an indispensable role in the overwhelming success of ARX sports cars.

About Honda Performance Development
HPD was founded in 1993 as the performance arm of American Honda Motor Company, to spearhead the company's entry into IndyCar racing. No other manufacturer has matched Honda's success in IndyCars, which includes 205 race victories, 15 drivers' championships, six manufacturers' championships and nine consecutive Indianapolis 500 victories (2004-2012). In 2013, Honda powered veteran Scott Dixon to four race wins and the 2013 IZOD IndyCar Series championship; and Tristan Vautier to series Rookie of the Year honors.

HPD's prototype racing efforts have resulted in more than 70 victories and multiple American Le Mans Series engine, chassis, team, and drivers' championships. The company's sports-car racing debut in 2007 at the 12 Hours of Sebring marked the first win for HPD's LM-V8 engine and the first for a Honda racing engine designed and developed outside of Japan. HPD won the LMP2 title in the inaugural 2012 World Endurance Championship and since 2010 has twice won the LMP2 category at the 24 Hours of Le Mans.

In 2013, HPD and Honda again swept the LMP1 and LMP2 manufacturers', engine, team and drivers' championships in the American Le Mans Series; while HPD-equipped Strakka Racing claimed the LMP1 private team class win at the 24 Hours of Le Mans.

HPD participates in competition on both two wheels and four. The company offers a complete line of race engines for cars from grass roots to pinnacle; for professional, amateur and entry-level racers. For more information about HPD and the company's racing and Street Performance product lines, please visit

About Wirth Research
Wirth Research is a fast growing innovative engineering company specializing in research, development, design and manufacture for the motor racing industry and other high technology sectors. Founded in 2003, the business pioneers the use of advanced in-house virtual engineering technologies, which enable the use of a complete simulated vehicle design, development and testing process reducing the need for wasteful manufacture of development models and prototypes. These include flow simulation and Computational Fluid Dynamics (CFD) services and a driver-in-the-loop simulator.

Wirth Research has a long-term partnership with HPD on the design, development and manufacture of the multiple championship-winning ARX sports car program. For more information about Wirth Research, please visit:

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    • 1 Second Ago
      • 1 Year Ago
      With the new Ligier JS P2 Coupe, the current HPD prototypes, the ORECA and Morgan stuff, it certainly sounds like P2 is still alive and strong and will continue to be so in 2015. Very exciting stuff for Prototype racing, honestly!
      • 1 Year Ago
      That's cool that Honda is still developing for sports car racing. It's a good looking P2 car too. I wonder if Muscle Milk Racing will switch back to Honda with this chassis for next year. They had soo much success with their old HPD car, they'd be silly not to at least consider it.
      Manoj Kusshwaha
      • 1 Year Ago
      what a nice blog and i really love this sport car If someone want to buy HID Conversion kit visit -
      • 1 Year Ago
      Too bad they wont make any sports cars.
      • 1 Year Ago
      " It's powered more IndyCar race winners and champions than any other manufacturer, hands down." While this may be true in the modern era, or the current naming iteration of the series, historically Offenhauser crushes them (especially if you add on Miller). Offys won 27 Indy 500's, including 11 years in a row where they swept the podium. It was the dominant engine for over 40 years. And this was in a time were there was far less restriction on engine choice (unlike today).
      • 1 Year Ago
      So, Honda, you CAN make nice sporty cars. Why are you holding out on us?
        Mike Laney
        • 1 Year Ago
        Because Honda doesn't actually design these cars, a racing design firm called Wirth Research does and Honda pays to slap their name on them.
      • 1 Year Ago
      The design imagination in this series continues to blow me away. It's too bad F1 moved to being such a "spec" series. Imagine what their vehicles would look like by now! And to think that once Acura changed their front wheels to match the rears it was the opening shot of all this design delirium.