The Mercedes-Benz name we know today was established in 1926. Before this date, Mercedes and Benz were separate brands, and that's how this Benz-Mercedes Rabbit-the-First became to be.
Owned by Jay Leno and featured on a recent episode of his online series "Jay Leno's Garage," the car was built in 1921 with the purpose of racing, using a Benz engine originally developed for an aeroplane and an old Mercedes chassis.
Leno describes this Benz-Mercedes Rabbit-the-First as a "low-flying aircraft." It's based on a 1908 Mercedes chassis, stuffed with a 1914 Benz 230-horsepower aero engine salvaged from a crashed World War I plane. The car is chain driven, and uses a period Mercedes transmission with a modern clutch.
At the turn of the century, airplane engines were like bigger, more powerful versions of car engines, so swaps like this were fairly common, Leno noted. The engine was indeed pretty advanced for its time, featuring four valves per cylinder. However, 1,800 rpm "is about the end of the world" when it comes to revs, according to Leno.
The car was built to run at Brooklands, lapping the British racetrack at 113 mph. Today, it will still do an "honest 100 mph," Leno said.
After its racing career ended, the car passed through numerous owners, with a restoration sometime in the 1960s. Leno said the car ran when he got it, but just barely. The steel cylinder water jackets had rusted, requiring a complex engine rebuild that included replacing the jackets with brass pieces.
The car also got some modern upgrades. The original drum brakes were also replaced with discs, and an additional cooling fan was added. However, the car retains its original oiling system, with a chain-driven pump and exposed drip cups that drench the driver in oil.
It ultimately took about 10 years of on-and-off work to get the car sorted. Watch the full video to see it in action on the streets of Los Angeles.