Audi Diesels Dominate Sebring

2006 Audi A3 3.2 quattro S-line by Conor Twomey Effortlessly good-but is it entertainment?

The first sound you caught was the rush of wind, then the whine of gears and the scrubbing sound of the brakes. The Audi R10 was already launching out of the corner before you heard the surprisingly deep and muted rumble of its big engine.

It took a bit of work to get used to the low, sleek racer that dominated the circuit at the 12 Hours of Sebring on Saturday. At first glance, the R10 looked a lot like Audi's older R8 racer - which has so far rolled up 61 wins during its 77 races - but the big TDI decals gave the first clue that this wasn't a traditional race car.

The R10 is, in fact, the first diesel ever to enter the grueling American Le Mans series. Under the R10's carbon fiber skin sits a 650-horsepower, V12 turbodiesel engine. While it's not the first time a diesel has raced, none has faced such a demanding environment.

"The main reason for developing the Audi R10 was to compete at the 24 Hours of Le Mans, as we want to be the world's first automobile manufacturer to win with a diesel engine," said Dr. Wolfgang Ullrich, director of Audi Motorsport, who described the development of the diesel racer as "the biggest challenge ever given to Audi Motorsport."

The two R10s entered at the 12-hour Sebring race seemed up to the task, quickly dominating the 3.7-mile course during practice and qualifying sessions, grabbing the two pole positions on race day.

There were clearly some "gremlins," admitted Ullrich, and Audi team members were visibly nervous as car number two failed to take its place on the grid as the cars starting lining up for the race's scheduled 10:43 AM start. As a drill team presented arms and the first words of the national anthem echoed across the course, the number two car finally launched from its garage, blasting around the track, but at that point, it had to settle for a spot at the end of the pack.

It proved to be nothing but a minor inconvenience.

As the green flag fell, the Audi number one car leapt ahead of the pack, immediately turning near-record lap times. The number two car, meanwhile, wove its way through the field of slower competitors, quickly climbing up on the leader board. By the time the harsh Florida sun shone directly overhead, it appeared likely to become little more than a two-car race.

But about five hours in, the leading, number one car suddenly pulled into pit lane, turned off into the Audi garage and was not to be seen again. Later that day, a clearly frustrated Emanuele Pirro, one of the car's three drivers, told TheCarConnection that the R10's telemetry system had failed, something that proved unexpectedly fatal, because it hid a problem quite literally brewing under the race car's carbon fiber skin.

The hot Sebring circuit had collected plenty of other debris by early afternoon, and the number one car was sucking some of it up. Ultimately, Audi mechanics peeled off a fist-sized ball of rubber from the car's radiator. Fearing it would overheat, and unable to monitor conditions, thanks to the failed communications system, the team decided to play it cautious, pulling the car from the race.

But that seemed only to encourage the drivers in R10 number two, especially Tom Kristensen, the Dane who had already scored three victories in Sebring and was going for a record fourth.

"I never expected to be where we are now," Kristensen had said, just prior to the race. It was a sentiment echoed by many of the other team members.

For years, few thought diesel power had what it takes to make it on the race track, where it today competes in only a few special niches. It's not that other teams hadn't tried.

In 1931, a Cummins-powered Duesenberg was the first diesel to run the Indianapolis 500. It finished well behind the leader, but set a yet-unchallenged record, running the entire race without a single pit stop. Cummins, today known for its long-running diesel truck engines, returned to the Brickyard several more times. In 1952, it fielded a racer fitted with what was described at the time as a "turbo supercharger." The entry had to pull out due to mechanical problems on the 71st lap, but the publicity sent Cummins sales soaring.

In recent years, privateers have fielded several diesels, including one at the challenging German Nurburgring. Meanwhile, a diesel-powered Volkswagen Touareg SUV - nicknamed Stanley - won the DARPA Challenge, last October. It was the first successful race of unmanned, self-guided vehicles, held in Nevada's Mojave Desert.

But Audi's effort, launched in 2004, underscores the dramatic changes in diesel technology that have made the high-mileage engines increasingly popular among motorists. In Europe, diesels now outsell conventional gasoline-powered vehicles, and Audi officials, including chief U.S. executive, Johan de Nysschen, believe a strong showing on-track, will help build demand in the States, where potential buyers remain reluctant.

The R10 uses a highly modified version of Audi's production turbodiesel technology. The V12 makes a whopping 650 horsepower and incredible torque - so much so that drivers had to hold back on the accelerator coming out of turns, lest they lose traction and, as happened during one frightening moment, send the R10 into a spin.

For drivers and spectators alike, the Audi's blinding speed was just one of several surprises. The other was the car's uncanny silence. It is so quiet, said Pirro, "you can't use sound to help you drive." Instead of listening for the engine note, he found himself having to rely on warning lights to properly judge shift points.

As night fell at Sebring, the only real question was whether the remaining R10 would be able to last long until 10:43 PM. Few things test the mettle of man and machine like an automotive endurance race. But as the clock along pit row counted down the minutes, it became increasingly clear that Kristensen, driving the final leg, would take the checkered flag.

Audi officials quietly conceded they'd decided to back off a bit, yet even as they fell back from their earlier lap times, the number two car shot across the finish line a good four laps ahead of its nearest competitor, triggering a barrage of fireworks over the Sebring track.

The two race cars will now be pulled off the Le Mans circuit. Audi engineers will study what they've learned, hoping to make the R10 an even stronger contender when it is put back in action in June, at the coveted 24 Hours of Le Mans. In the meantime, the older R8s will be fill in.

Some would argue that simply grabbing the pole slot was enough to justify Audi's effort, but Saturday's performance is likely to get a lot of folks thinking anew about the potential of the diesel. And that includes American motorists, looking for a way to improve their mileage with the latest in automotive technology.

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