This week, each team has to convert a two-tonne, ten-mile-an hour milk float into a tyre smoking dragster. Leading the Red Team again is the Prince of Pressure Steve Garfirth, a specialist in hydraulic engineering. The Blues’ skipper is Ed ‘The Professor’ Rycroft, who develops performance-handling technology for a top car firm. They must use as much of the milk float’s materials as possible in their new designs, but also have a kitty of £500 for any extras they wish to bolt on. After four days of building time, their conversions will be brought to a drag-racing strip where they will take part in a head-to-head challenge. The best of three will win.