Putting a tiny engine in a hairy-chested sports car doesn't seem like the perfect recipe for fun, but British sports car companies have always been a little... different.

Caterham is one of those companies. Back in 1972, it bought the rights to Colin Chapman's lightweight Lotus Seven sports car, and has produced variations on the theme ever since.

The latest slots a miniscule Suzuki-sourced 660cc turbocharged gasoline engine under its long hood.

That sounds quite familiar to us. 660cc is the maximum engine capacity limit for Japan's kei-car regulations--rules that ensure Japanese drivers without a parking space can still own a car, albeit a tiny, usually boxy and space-efficient one.

Only one kei-class car is currently sold in the U.S--the Mitsubishi i electric car. And even that has been widened and lengthened to suit larger American frames, which gives you some idea of how small the average kei car is.

Doesn't sound very sports-car-like, does it?

Here's where things get interesting. First, despite the restrictions associated with kei cars, Japanese automakers aren't beyond making tiny sports cars that just happen to fit these regulations to the letter. It's seen some quite spectacular little cars emerge from the island, like the Suzuki Cappuccino, Honda Beat and Autozam AZ-1.

Secondly, these cars can be quite quick, owing to their low weight and tiny dimensions.

Low weight and tiny dimensions have long been a hallmark of the classic British sports car, which brings us to the Suzuki-engined Caterham Seven. The existing entry-level Seven weighs just 1,200 pounds, and with a mere 125 horsepower to its name can still clear the 0-60 mph sprint in under 6 seconds.

Caterham Technology & Innovation promises the new car is even lighter. And while kei car regulations usually restrict power to 64 hp, the little three-cylinder lumps are also rather tuneable, so performance shouldn't be a problem.

And the final benefit? Fuel efficiency, of course. While Caterham reveals no figures, and the Seven lacks sleek aerodynamics, cruising efficiency should still be relatively impressive--it's lighter than virtually any other road car, after all.

The new, three-cylinder Seven will launch--in the UK only, naturally--in the Fall, with first deliveries before the end of 2013.


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