Through the 1950s and 1960s, a horde of little cars competed at Le Mans for the Thermal Efficiency Index prize. The idea of this formula was to reward those who tried for performance without using oceans of fuel and the competing cars were invariably small, ultra-streamlined and powered by tiny engines. I have always felt that the drivers of these little wonders must have been very brave to head down the Mulsanne straight at their maximum 120 mph or so with the big cars screaming past at close to 200 mph.

A consistent entrant and winner of the class was the small French firm, D.B. Рthe initials indicating the partnership between two designers, Charles Deutsch and Ren̩ Bonnet. When the pair split up in 1962, Bonnet started building cars under his own name with Renault supplying the engines.

And so was born one of the prettiest little GT cars ever Рthe Ren̩ Bonnet Djet. It was one of the first production mid-engined cars and, thanks to its light weight, was as zippy as it looked. With only one liter of engine, it still managed a top speed of about 110 mph. Most were bought for racing in spite of being intended for road use.

By 1965 M. Bonnet was in financial difficulties and sold out to Matra, who continued production of the Djet and eventually rebodied it with one of the ugliest designs ever. As a result, the original Bonnet Djets are still regarded as the real thing.