C5 Twenty Five

Also from Issue 48

  • C6.R replica
  • 1966 restomod
  • Marcos TSO-GT2
  • Market Report: C1/C2
  • 800-bhp Supercharged C6
  • 1968 big-block convertible
  • Ex-Lou D’Amico C2 racer
  • How-To: Steering box rebuild
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Nevertheless, endurance racing presents a unique set of challenges; durability, not speed, is the priority. “We just haven’t tested enough,” admits Pfadt crew chief Todd Imwald, watching the Corvette pull off the track. “We’re essentially running a sprint car, set up for shorter races, so there’s a steep learning curve.” Like most of the Pfadt team, Imwald is businesslike but jovial, and his good-natured sense of focus reminds us more of a professional crew chief than an amateur one. But a race like the 25-hour requires something more than just the right approach. “The car is fast enough,” Imwald says, “it’s just a question of making it live.”

Unsurprisingly, by the time the Pfadt team is done repairing the car’s fuel system, most of Thunderhill’s paddock is in disarray. Tools and parts are scattered everywhere, and more than a few cars have run into trouble. A late-’90s Pontiac Firebird is being loaded onto a trailer, a thick trail of oil leading to its nose. Two Miller Cup Ford Mustangs are up on jack stands, permanently parked. Wrenches are being turned and crash damage is being hammered out.

For the Pfadt team, things are finally turning around. As the sun sets, Imwald is standing on the pit wall, listening intently to the radio; he’s joined by the team’s fourth driver, a Corvette club racer from the Pacific Northwest named Dean Conti. The C5 flies down the front straight, slams into the first corner and slingshots through a group of slower cars, a bellowing howl echoing out its exhaust. Popp is driving. After watching the crippled Corvette limping around the track for hours, seeing it flogged flat-out by a gifted driver—and Popp, a former NASA champion, is just that—is downright hypnotic.

“That’s Danny for you,” Imwald remarks with a grin. “He’s saying that the car doesn’t have that much power; he just turned a 1:50.” Conti laughs, saying, “If he’d pulled that in qualifying, we’d have been third on the grid.”

The high times don’t last long, however. Shortly after six o’clock, just seven hours into the race, the corner workers wave their red flags. In the space of less than 20 minutes, a blindingly thick, syrupy fog has descended onto the track, reducing visibility to mere feet. Thunderhill’s front straight is suddenly an impenetrable gray wall. You hear the cars before you see them, the fog moving and swirling ominously, until—wham!—something with headlights explodes past you, only to immediately disappear back into the whiteness. NASA officials indefinitely suspend the race on grounds of safety. The cars are parked.

Things crank back up again at five o’clock the next morning. The fog has dissipated some, but it’s still present, draped over the track like stretched-out cotton candy. All told, the red-flag delay lasted some 11 hours, and while NASA officials have postponed the race’s end by three hours to try and compensate, this won’t help the Pfadt team. It’s mid-morning and the Vette is parked in the paddock, stationary and cold. Aaron Pfadt and the rest of the crew retire to the support tent to have breakfast.

“We went back out [at the restart], and the car ran great for a while,” Pfadt says, smiling ruefully. “Then it started to pick up a miss. We pulled the car in, we cleaned the fuel filter and we back-flushed the injectors. After that, it was perfect—the car was making full power, the lights were working great in the fog and I was just flying. And then the clutch started slipping. It’s frustrating, because we were phenomenally quick. I turned a 1:51 in the fog with the clutch slipping.”

The car is done.

For Pfadt, the race has been a study in frustration, a textbook example of how learning from your mistakes is rarely a calm and relaxing process. Some problems, like the fueling issue, are simply the result of bad luck—the team eventually discovers that a supposedly gasoline-proof sealant used on the fuel tanks’ quick-fill system decomposed in the presence of gas, filling the fuel lines with debris. Other issues, like the slipping clutch, are traceable to oversight. “The clutch had too many hours on it [before the race],” admits Imwald, “and it was just time for it to go.” Setbacks like these show how difficult it is to make a racing car—any racing car—go the distance. Even with huge amounts of skill, experience and resources, there are still countless things to go wrong.

As for the lessons learned? The overall win went to a Mazda MX-5, a car that lapped the track roughly 10 mph slower than the pole-sitting prototype. Most of the faster, front-running cars broke or crashed out, proving that speed and endurance aren’t natural bedfellows. And adding insult to injury, when the Pfadt Corvette briefly returned to the track to take the checkered flag, a slower car crashed into its left front corner, breaking a suspension upright. It was almost as if God himself wanted the car off the track.

Done, but not defeated, the Pfadt team begins to pack up. Aaron Pfadt finishes his breakfast, gets up from his chair and looks out at the track. Will he return next year? “It’s hard to come back,” he says, “but then, it’s hard not to come back.”