Lotus isn't the only British company renowned for building super-lightweight sports cars. For nearly 40 years Caterham has been building lightweight track cars based on the legendary Lotus Seven after it ended production in 1973. A new era for Caterham recently begun as the company is now owned by Japan's VT Holdings.

Since it launched, Caterham has continually improved the Seven, making it lighter, more powerful, and more agile. Now, Caterham has unveiled the lightest production Seven ever made: introducing the Seven 170. A successor to the entry-level Seven 160, the Seven 170 weighs just over 970 pounds. As well as the lightest, it's also the smallest current Seven.

With new front and rear wings, the new Seven 170 is only 57.8 inches wide, making it 4.1 inches narrower than any current Caterham car. It's so compact that the Seven 170 complies with Japanese Kei car regulations.

Powering the Seven 170 is a 660-cc turbocharged three-cylinder Suzuki engine producing 84 horsepower and 85 lb-ft of torque. That might sound modest, but thanks to its lightweight construction, the Seven 170 boasts an impressive power-to-weight ratio of 170 bhp per tonne. Thanks to its exceedingly low weight, the Seven 170 will sprint from 0-62 mph in 6.9 seconds and max out at over 100 mph. Its lower weight also helps reduce emissions. With a CO2 figure of 109g/km, the Seven 170 is Caterham's greenest sports car yet and is even more efficient than some hybrid cars like the Toyota Yaris 1.5.

Available as either a complete kit or factory-built, the Caterham Seven 170 is offered in two trims: the 170S and 170R. Designed "for the more laid-back driver," the 170S comes with a five-speed gearbox, road suspension pack, 14-inch Silver Juno alloy wheels, and a windshield. It also comes with black leather seats, a Momo steering wheel, and four available paint colors.

The track-focused 170R also features a five-speed gearbox but adds sport suspension, 14-inch Black Juno alloy wheels, composite race seats, a four-point race harness, limited-slip differential, and a carbon-fiber dashboard. As a kit car, the Caterham Seven 170 starts at £22,990 ($31,495).

"The Seven 170 really distills the brand's reputation for offering accessible, simple, light-weight sports cars," said Graham Macdonald, CEO at Caterham. "Given the popularity of the 160, we're really excited by the potential the Seven 170 offers customers. We've taken what was great about the 160, its performance and competitive price, and built on it by adding even more choice for our customers. We're confident the inclusion of the 170R, not previously available on the 160, will prove a hugely popular specification for both new and old customers."