The 25 Hours of Thunderhill is the longest road race in America, but only if you are running at the end.

To do that, you have to be ready when it starts. And that was the challenge before us, as we huddled beneath the glow of a pair of high-intensity lights, methodically gutting a MoPar V-8.

During practice for the race, the engine in the Dodge Charger ran strong. And it ran cool. But it kept blowing water out of the radiator catch tank, soaking the engine bay and lubricating the left front tire. There was no water in the oil and no oil in the water. Even after the engine cooled down, the system held pressure. We tried a lower water level. We tried a higher one. We burped the engine. We checked for flow and restrictions. Nothing changed but our level of frustration.

Finally, there was no other option. We began tearing apart the engine, knowing we didn't have the parts on hand to put it back together. We had already dispatched drivers to distant parts houses in search of what we needed, and we knew we'd have a couple hours of daylight the next morning to finish the job.

The "too stubborn to admit you are licked" mindset is the essence of endurance racing, competition that can be as tough on the crew as it is on the car.

Perhaps the hardest endurance race in the country is the 25 Hours of Thunderhill. The 3-mile road course sweeps up hills and charges into the valleys of rolling agrarian landscape. It's a 14-turn track that can be hard on brakes, clutches, gearboxes, and bodywork.

Consider that the car that won the race in December covered 760 laps, for a total of 2,280 miles. That's four and a half times the length of the Daytona 500, or enough miles to go from Charlotte to Los Angeles in just over a day.

Sixty-six cars started the race, and when the checkered flag fell, the winning car had lapped the Second Place car 23 times, making thousands of passes on slower cars-and more than half the race was run in darkness-in the process.

We were relative rookies running in the major leagues. The list of drivers included well-known names in the road racing crowd: Indy 500 veteran Lyn St. James, former Champ Car driver Dominic Dobson, road-racing icon Randy Pobst, and others with multiple trips to Le Mans, Sebring, and the 24 Hours of Daytona.

Few teams elect to race stock cars in endurance events. The chassis aren't nearly as sophisticated as what comes out of the factory at Porsche or BMW, and the big V-8s have an appetite that keeps the fuel crew scurrying between the pits and the gas pumps. And the price tag for the 500 gallons of fuel we planned to use was dwarfed by the bill for 13 sets of tires we mounted up for the trip.

Unlike the nimble sports cars they share the track with, stock cars don't adapt well to the tight turns and long straights, off-camber corners and hairpin turns. Tires? The Goodyears run out of steam just about the time the drivers do.

But in spite of their drawbacks, the cars are impressive on-track. They are big and loud and all eyes and ears follow them as they charge down the straight past the pits. Surrounded by Miatas, Porsches, and Acuras, the big Charger looks like someone invited a linebacker to ballet class.

What the car lacked in finesses, we hoped to make up with muscle.

And does it draw attention. Jaws dropped when the crew dropped the trailer door to roll the multi-colored MoPar onto the tarmac. In a paddock populated by high-revving four-cylinder imports, it was impossible to ignore the throaty thunder of the Dodge Magnum when it fired up.

The Dodge wasn't the only full-bodied car at the nation's longest race. We were pitted next to a pair of V-8-powered pickups and a second stock car was parked about 20 spots from our pit spot.

Our car was built for the Great American Stock Car Series, a Portland, Oregon-based operation that runs both ovals and road courses. It pounded the wall at Iowa Speedway early in the 2009 season and came back to the GASS shop for a new front clip.