C5 Twenty Five

Corvette suspension specialist Pfadt Racing heads to the world’s longest endurance race. We tag along.

April 1, 2009

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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Danny Popp looks out over the pit lane, sets his tools down and sighs. The sleeves on his driving suit are pushed up to his elbows, dark circles frame his eyes and he’s wearing a greasy pair of Mechanix gloves. Every two minutes, a silver C5 thunders past the pit wall; even if you’re not watching, you can feel it whomp by the start/finish line. The vibrations make your toes tingle, but Popp doesn’t flinch.

Five minutes later, the Corvette dives onto pit road and jerks to a halt in front of Popp. Aaron Pfadt, a compact, brown-haired Midwesterner with a boxer’s build, climbs out of the driver’s seat. He helps Norm Goldrich, a Porsche club racer from Ohio, strap himself into the car, and the Corvette tears back onto the track.

Two minutes later, Goldrich is on the radio: The Corvette has developed a few handling quirks—too much oversteer in some of the faster corners and an annoying rear-end twitch under braking—that didn’t exist in testing. Making matters worse, the steering rack began leaking during Pfadt’s stint, so Goldrich, like Pfadt before him, is forced to strong-arm the car around the track without power steering. And, troublingly, one of the corner workers has reported white smoke coming from the Corvette’s exhaust.

Pfadt looks at his crew chief. The clock on the starter’s stand reads 24:09:22—24 hours, nine minutes, and 22 seconds left to go. Problems this early in the race are not a good sign.

“Just tell him to drive through it,” he says. “If the car is safe, even if it’s miserable, run laps. Just keep going.”

Racing improves the breed, as the old saw goes, but what that pithy little aphorism doesn’t tell you is that racing also breaks things in ways that you couldn’t have imagined, or that it requires constant, skilled planning and engineering to keep everything from ending in an oily mushroom cloud of doom. Finishing first, as experienced hands will tell you, requires that you first finish, which requires that you stay one step ahead of anything that might go wrong. And the longer the race, the more things there are to go wrong.

Consider, then, the 25 Hours of Thunderhill. Held every December at Thunderhill Raceway Park, just outside of Willows, California, it is the world’s longest closed-course endurance race—and yes, that’s a fact, not just a marketing slogan. It is exactly one hour longer than the famed endurance events held at Le Mans and the Nürburgring, and like those events, it’s known as a car-killer. Most of the teams that roll into Thunderhill’s paddock come prepared: Bringing everything from spare engine blocks to entire spare cars is considered reasonable and prudent planning.

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