width=466On September 1, the Collier Collection of Naples, Florida, brought to Lime Rock its 1939 Mercedes-Benz W 154 Grand Prix car. (Yes, Collier's is a collection, not a museum. Don't bother looking for a website; visitors by invitation only.) The word from Lime Rock's PR person: this would be the first time the engine had ever been started on a racetrack in 69 years and 363 days, having last run in anger at a minor street race in Yugoslavia on September 3, 1939, two days after the start of World War II. Two ringers from Stuttgart had been sent to Connecticut to help with this historic ignition, as had the British restorer who'd rebuilt the engine. The Collier guys also planned to run the car on the track briefly, which, it was said, would also be a 70-year first.

width=398Legend has it that this car, the last of the 15 W 154s built, was one of two found in 1945 in Austria by the steamrollering Soviets, who put them on a train to be shipped back to Russia. The cars got as far as Romania, where the troops running the train traded them for liquor, food, local goods and probably a few cute Romanian girls.

I missed that phrase on a racetrack in my quick reading of the invitation to attend, so I hustled up in my nearly-as-ancient 911 to see and hear what I figured would be something as momentous as being present at the opening of King Tut's tomb. Would it start? Would it grenade? Would they need a spritz of snowblower ether to bring it to life?

Well, it was fun but not quite as historic as I'd expected. Turns out the car had actually raced several times well after World War II, the last time in a hillclimb where it wrecked. And when the engine started with a brain-melting bark on the second turn of the crankshaft, it immediately became obvious that Mister W 154 had been run, after an extensive rebuild, plenty long enough to jet and tune its V12's supercharged carburetors. Just not on a racetrack.

width=398While dozens of us crowded around, snapped pictures and generally got in the way, plugs were pulled, a crystal-meth lab's worth of fuel was poured, the engine was spun to build oil pressure, plugs were replaced (without a torque wrench in sight, by the way; these guys have calibrated wrists). A friend who was with me laughed and said, I have to go through this every time I start my '40 Fleet biplane, but nobody's ever around.

Came the big moment and instantly the air was filled with unbearable noise and the smell of a model-airplane meet. Emissions? You betcha: little did the tiny village of Lakeville, Connecticut, know that it had briefly become an EPA Superfund site. The engine burns a blend of methyl alcohol, nitrobenzene, acetone and sulphuric ether that would probably burn through concrete.

After five minutes of WHAP . . . WHAP . . . WHAP . . WHAP back and forth to 4,000 rpm (to keep the hot start-up plugs clear), the entire car was gently smoking as restorative paint melted here and there, asbestos wrapping burned off the two tailpipes and glycol began to bubble into the tray under the car.

width=398In go the cold plugs, from a gray wooden box on a cradle fitted to the curve of the car's cowling and lettered von Brauchitsch, who drove it at Belgrade that September day in 1939, starting on the pole and finishing second to Nuvolari in an Auto Union Type D.

The car is pushed to the end of the pit lane while a dozen well-heeled Lime Rock Park Club members wait impatiently for their turn at the track. One of them, trim in his tailored shorts and Ralph Lauren shirt, in an accent that we used to call Locust Valley lockjaw, had earlier asked me, Are you here for the track day? I told him, No, I am a writer, waiting for the Mercedes. Yes, I figured, he said as he eyed my stock Levi's.

The W 154 did a few racketing but careful laps on its cold, skinny tires, the Mercedes Classic Center factory driver obviously well aware of the I'm-guessing $20 million value of the car. If you want to see this Silver Arrow do it again, go to the 27th Annual Lime Rock Park Vintage Festival this Labor Day weekend. It'll be there. Bring earplugs. Or watch the video here.