"If you're a performance brand, you have to go racing. It's that simple," says Acura's CEO.
Acura has lifted the lid on the all-new ARX-06 prototype, an electrified race car itching to do battle in a series of motorsport events, such as the 2023 IMSA WeatherTech SportsCar GTP Championship. The dramatically-styled racer is powered by a twin-turbocharged 2.4-liter V6 which gains extra motivation from a hybrid power unit.
Developed by Honda Performance Development, the AR24e motor is the smallest combustion engine ever created by the department for endurance racing but still boasts strong performance figures. Combined outputs meet the required targets of 500 kilowatts (670 horsepower) while revving out to 10,000 rpm. The compact design and 90-degree V-angle allow for a lower center of gravity, improving handling and dynamics.
The bespoke racing V6 has been engineered to run on a sustainable low-carbon fuel. "We've gone in a new direction for HPD in the design of the ICE," explains Pierre Descamps, who led the powertrain design team. "It is still a V6, which, of course, for Honda is well known. We have incorporated several new elements which we believe will make [the] best use of the electric Motor Generator Unit (MGU) and battery pack.
As per IMSA-ACO requirements, the MGU has been supplied by Bosch, while the battery pack comes courtesy of Williams Advanced Engineering.
Additional requirements specify that manufacturers choose from four pre-selected prototype chassis designs. Acura has elected to work with trusted partner Oreca, with which it shares a strong relationship and history. "They've been great partners throughout both our ARX-05 DPi program and now with the ARX-06," said HPD's Mark Crawford. Oreca and HPD worked closely to simulate chassis layout geometries and even embarked upon lap time optimization studies.
The racer was even coded into a simulator to develop the dynamics and various control systems. Speaking of the latter, HPD created the control system for vehicle dynamics, the hybrid powertrain, and brake-by-wire operations, all of which were later implemented on an F1-style ECU hardware platform. The chassis itself is a carbon fiber monocoque design.
"Working with the extremely talented Oreca engineers on chassis, aero design, and powertrain installation has been a real pleasure. Both groups have put their heart and soul into this ... sophisticated race car," added Crawford. Acura took an interesting approach when it came to the exterior design of the ARX-06 prototype.
The same people who were responsible for the Integra and NSX were called in to create the initial sketches. Once the team settled on a design, scale models were produced for aerodynamic and wind tunnel testing. The result is a wind-cheating shape that retains Acura design cues. "We treated it as an integral part of our lineup," explains Dave Marek, executive creative director.
Even the drivers were consulted. Using VR headsets, they were able to give feedback on the cockpit. After recommending a lower placement for the side mirrors, Acura redesigned this small feature and not only improved visibility but aerodynamic efficiency, too.
Under the skin, the suspension setup comprises double wishbone, pushrod suspension at the front and rear, with Penske dampers.
The prototype racer will make its debut at the Rolex 24 at Daytona, where it will do battle with vehicles such as the Porsche 963, which is powered by a 4.6-liter twin-turbo V8. BMW's M Hybrid V8 should also prove a worthy adversary to Acura's racer. However, Acura's continued motorsport efforts are about so much more than bragging rights, notes Jon Ikeda, Acura brand officer.
"If you're a performance brand, you have to go racing. It's that simple." Duking it out with brands such as Porsche and BMW is just about the best marketing Acura can receive. Not only will it give the automaker greater presence, but it may be the driving force for would-be customers to consider a vehicle like the new Integra, for example.
"We are very cognizant this is a big step for us. We have a lot to learn, but that is why we race," notes HPD president David Salters." Now the challenge and hard work really starts, including grueling 24-hour simulations, and learning how to maximize all aspects of performance." Perhaps lessons learned in the development of the ARX-06 will be employed in future performance vehicles from both Honda and Acura.