Acura officially took the wraps off its new LMP1 contender Monday night at Sebring during a media launch event, which included a no-holds-back view of the ARX-02a. While the open-top, V8-engined machine may appear conventional at first sight, it's fact quite revolutionary, in which chassis designer Nick Wirth calls a "sportscar on steroids."
It's all in the tires, and Wirth Research has come up with an innovative way it believes it can topple the diesel stranglehold LMP1 has seen for the last three years. Thus, the ARX-02a is designed for full-sized rear tires on all four corners of the car, providing an estimated 7 percent more contact patch area to the racing surface compared to a conventional P1 machine.
"How do you fight with the diesels with a petrol-powered car? Well you have to do something out of the box, something very different," explains Erik Berkman, president of Honda Performance Development. "We conceived of this idea to put bigger front tires, under the rules, on the front of the carI. Our concept was born out of a desire to go racing in P1, but born out of the necessity of taking a gasoline engine and punching it out into the rules."
British-based Wirth Research, which is responsible for chassis construction and development of the new Acura, utilized advanced computer simulations to design the car almost completely away of the wind tunnel. Wirth says the ARX-02a has been engineered to the standard of a Formula One car, but only by 10 people and on one-twentieth of the budget.
There have been some challenges, though, including creating the perfect balance. With larger wheels, it makes a challenge generating downforce in the front-end, but the ARX-02a has been optimized for aerodynamic efficiency, with the suspension better integrated to provide room in the front for the 1.5-inch wider tires.
Weight was also a crucial factor in the development of the ARX-02a. Wirth says the chassis carries a significant amount of ballast to meet the minimum 900kg weight. Components like the gearbox are considerably lighter, and only the parts carried over from last year's P2-class ARX-01b were the headlight bulbs and wheel nuts.
"Nobody has tried a similar concept to my knowledge, so we're learning how to get the best out of this car," said de Ferran Motorsports owner/driver Gil de Ferran. "We're making significant steps forward every time we run. It's a work in progress; we're still very much in the early stages of this project. We could always wish we had more time, but we're certainly looking forward to meeting Audi and Peugeot over here."
Acura has retained the philosophy of its proven V8 powerplant, increasing the displacement to 4.0 liters, which can now crank out 620 bhp. The normally aspirated engine, dubbed the Acura LM-AR7, was one of the many components shown out in the open Monday night, as mechanics uncovered the ARX-02a for the whole world to see.
Both de Ferran Motorsports and Patron Highcroft Racing will debut the new prototype at the season-opening Twelve Hours of Sebring, going up against Audi's new R15 TDI and Peugeot's 908 HDi-FAP diesel-powered machines. The challenge, though, will be to run a trouble-free race, something Berkman is hopeful come March.
"The biggest concern with an all-new car is: will Sebring bring us to our knees and make us break, or will be we be able to survive and make it to the end?" Berkman said. "That's that real question now so we just have to keep banging out the miles and get ready for the race."
Berkman added the fact that due to Audi's withdrawal from the series, Acura will slow development work after the Twelve Hours, due to lack of competition. That option is much better than others discussed, as Berkman admitted that there were once considerations of only running one race this season. But instead, the brand has reaffirmed its long-term commitment to the series.
"Until Sebring we have a full court press to try and eradicate all the bugs," Berkman added. "Again, it's not so much a search for speed than it is to map out the car, make sure under all conditions we have an answer for setup and knowing how tires will wear. After Sebring, the pace of development will drop from what we originally planned when we thought there would be more competition."