In a world where an "exciting" new limited edition often means an exclusive colour and a few extra options thrown in, Caterham has broken the mould with the CSR Twenty, celebrating 20 years of the CSR chassis.

Powering the CSR is the most popular engine Caterham offers: the naturally aspirated 2-litre Ford Duratec engine from the Seven 420, creating a combination not previously seen in the Seven. The 210bhp is enough to propel the 620kg flyweight to 0-60mph in 3.9 seconds and on to a top speed of 136mph. Transferring power to the road is a five-speed manual gearbox. Bringing the CSR to a stop are ventilated front discs with four-piston callipers.

CSR stands for Cosworth, Seven, Road and Racing, denoting Caterham’s most sophisticated chassis, which features inboard front suspension as well as a fully independent rear setup to help glue the car to the road.

It’s not just the performance that’s been upgraded; the fit and finish of both the exterior and interior are the most premium ever seen on a Caterham, solidifying its position as a road-biased setup rather than a track toy. The exterior features a 620-inspired nose cone and front wings, LED front and rear lights, black Mohair boot and weather gear, red brake callipers, a two-tone Union Flag grille and exclusive 15" Vulcan alloys. The CSR Twenty comes in two exterior colours: Kinetic Grey and Dynamic Silver.

The cockpit is finished with a satin carbon dash, exclusive CSR Twenty dials, a premium leather tunnel, Alcantara gearstick and handbrake boots, and a traditional Momo steering wheel in leather. In a rare move, each car will have a numbered plaque between the seats. The CSR Twenty’s seats are finished in a blend of leather and Alcantara inserts with red stitching and CSR Twenty logos.

All of this does not come cheap, however — the one limited edition convention the CSR Twenty does comply with is a hike in price — in this case, to £79,995. While this is certainly a considerable sum for a Caterham Seven, as per its name, only 20 CSR Twentys will be made for the UK market, with another 20 heading across the Atlantic to the United States. Each one will be built in Caterham’s brand-new Dartford factory.