If you were around in the 1950s, you’ll recall that it was an exciting time in the growing sport of late-model stock-car racing.  
Starting grids were filled with more different makes of cars than we have seen in race lineups since that era: Buick, Oldsmobile, Lincoln, Pontiac, Ford and Mercury, Chrysler, Hudson, Studebaker and Nash. Of all the makes, Nash was the orphan and oddball. You may remember the popular gag line: “You can drive it all day, sleep in it at night, and turn it over in the morning and take a bath in it.” The “bathtub” Nash was the Rodney Dangerfield of the car world — it didn’t get no respect. And its small straight-six engine, at just 234 cubic inches, seemed woefully outclassed.
It surprised many when Bill France, Sr. selected the unlovely Nash as the first official car of NASCAR. But France seldom had only his arm up his sleeve. He undoubtedly negotiated a solid sponsorship with the Kenosha, Wis., carmaker, and he set about creating publicity for them immediately.
France’s driver of choice in those days was the talented Johnny Mantz, who in 1950 won the first Southern 500 at Darlington (S.C.) Raceway, driving a little Plymouth coupe owned by France. The car used heavy-duty truck tires, and was rumored to have some Dodge truck running gear.
 In 1951, Mantz’s first assignment with NASCAR’s new official car was to drive the “bathtub” to a new stock car speed record of 102.461 miles per hour, in a NASCAR-sanctioned two-way run at El Mirage dry lake in California. It broke a record set the year before on Daytona Beach by an Oldsmobile.
In 1950 IMCA, the nation’s oldest sanctioning body, crowned Herschel Buchanan its national stock car champion. He drove a 1948 Nash Ambassador coupe to the title against strong fields of Oldsmobiles, Buicks, Lincolns, Hudsons, Fords, Mercurys and other makes. At one point in that busy season, Buchanan won eight straight 100-mile events.
 Even the lowly four-cylinder Nash Rambler got into the act: well-known New York driver Tony Bonadies won a 100-mile dirt-track event at Lanham, Md. He was the only driver among the 25 entries to go the distance nonstop.
Perhaps the most astounding performances recorded by the straight six-powered Nashes were on the tough six-night-a-week short-track wars in the Chicago area, where the action was rough and tumble, and the drivers far ahead of other areas of the country in setup, handling and tires.  
Bill Van Allen was season champion at 87th St. Speedway on the asphalt, and a multiple-time champion on the dirt at Santa Fe Park, driving Nashes by Larry Moisan. And at Raceway Park in Blue Island, billed as “The World’s Busiest Track,” the remarkable Bud Koehler was the perennial champion, amassing 490 career victories and 11 track championships, many of them in his familiar No. 77 Nash “bathtub.”
Also in the 1950s, the Mortenson brothers of Minneapolis ran an IMCA sprint car billed as having a “Lycoming boat engine.” It was in fact a Nash six. When it was right, the car was fearsome, and would accelerate with an Offy.  But the Mortensons were experimenters, and they radically over-cammed and funny-fueled the car, and it was not a consistent finisher.
What was the secret of Nash racing success?  
Although the engine was small, it was superbly designed, with a bulletproof seven-main bottom end, a long stroke, and a meaty block that could be punched out to about 250 inches (Chicago car builder Larry Moisan told me he bored his engines to take Hudson pistons).  
The Nash cylinder head was the piéce de résistance. One old-time race engine builder called it a “see-through” head: if you took the intake manifold off one side, and the exhaust off the other, you could literally look through the head. With the right cam, he said, they were a “breathin’ fool.”
With the mid-1950s introduction of the auto industry’s over square OHV V-8s, the days of Nash’s “little engine that could” were numbered, but their colorful record in racing during that era still stands as a remarkable achievement.