The Daren Mk.3 is the third sports prototype racing car built by Daren Cars (now Hydrautug).

Daren Cars was founded in 1967, and first produced a car in the Mk.1 in 1968. John Green built the car for racing based on a Merlyn MK11 Formula Ford. The car would be so successful, winning 4 races, that John Green started getting requests to build more Mk.1's, and as such the Mk.2 was born, with only one Mk.1 ever being made. The cars were made with a "Martin" branded Cosworth FVD engines, with 8 being made between 1968 and 1970. In 1970, Daren started development for the Mk.3 as based on the Mk.2, but now fitted with a BRM V8. Six Mk.3s would be built, with an original selling price of £2,500 as a rolling chassis (no engine or gearbox). The BRM V8 used in the car is bored out from stock 2.58 mm (0.102 in), upping the total displacement to 2,136 cc (130.3 cu in) for a total bore and stroke of 71.08 mm × 50.8 mm (2.798 in × 2.000 in).^[1][2][3]