Not to be confused with Chrysler's old "K Car" platform. Dating back to 1949 in Japan, the Kei designation offers some of the tiniest vehicles that could still be legally considered a car. In Japan, and other East Asian countries, vehicles are often subjected to tax rates based on their external dimensions and engine displacement, and Kei cars are made to be registered as cheaply as possible. So they squeeze as much practicality, or fun, out of a miniature frame as is possible.
After World War II, much of the general Japanese population was faced with poverty, and they could hardly afford basic transportation. The newly rebooted government responded to the issue by creating the Kei classification vehicle, meant carry up to four people while costing not much more than a motorcycle. These first Kei cars were limited to sizes of 117 inches long, 40 inches wide, and 80 inches tall. Engine displacement meanwhile had to be under 360 cc. That's about one third of one liter!
Numbers that small are unfathomable to American tastes, but the class proved to be quite popular in urban Japan. Devilishly simple, many of these cars through the 50's and 60's were powered by air-cooled two stroke twin cylinder engines. The most noteworthy of these early Kei cars is perhaps the Subaru 360, which actually found some buyers here in the United States. In 1970, Suzuki also created the Jimny Kei truck, later being sold being sold as the Samurai in the US through the 80's and 90's.
Over time, regulations on the Kei class loosened slightly, allowing up to 129 inches of length, 55 inches of width, and .66 liters of displacement in 1990. This set in motion a golden age of Kei car production. Unlike decades prior, Japan was rife with economic prosperity in the 90's, and even their cheapest cars reflected that. It's at this time that Kei sports coupes and hot hatches were created. Suzuki and Mazda added turbochargers to boost their little three cylinder engines to a limit of 63 horsepower.
The Suzuki Alto hatch even combined turbo power with all wheel drive. Meanwhile, Honda powered its mid-engine Beat roadster with another three cylinder plant using individual throttle bodies to rev over 8,000 RPM.
Around the same time, Kei vans and truck became increasingly popular. These manage to pack a ton of cargo into such a small package, thanks to their cab-over design. Through the 90's many Kei trucks were even purchased by farmers in the US, and were well-respected workhorses thanks to their rugged simplicity.
Nowadays, the 660 cc limit remains, and the once-hot segment has cooled down quite a bit. The only real Kei sports car left is the Honda S660. That mid-engine successor to the Beat was released in 2015, but production is now set to end a year from now. As with other markets, it seems the Japanese public is jumping into larger segments, and the Kei class is being left behind. Perhaps the government could help reinvigorate it by punching out engine displacement to a full liter, and by doing away with the now-sluggish 63 horsepower mandate.
If you're really interested in Kei trucks, stay tuned, because The Starting Line will soon be taking delivery of Honda Acty and Subaru Sambar flatbeds. There will be featured articles for those, as well a photo galleries coming up in the next few weeks.