The major changes involved installing the 1,557 cc (105 bhp (78 kW 106 PS)) engine, together with the same close-ratio gearbox as the Elan. Ford supplied the 2-door Cortina bodyshells and took care of all the marketing and selling of the cars, whilst Lotus did all the mechanical and cosmetic changes. The Type 28 or Lotus Cortina or Cortina Lotus (as Ford liked to call it) was duly launched. Chapman quickly accepted, although it must have been very busy in the Cheshunt plant, with the Elan about to be launched. Whilst the engine was being developed, Walter Hayes (Ford) asked Colin Chapman if he would fit the engine to 1,000 Ford saloons for Group 2 homologation. This was in order to get the car closer to the 1.6 litre capacity class in motorsport. Almost as soon as the engine appeared in production cars ( Lotus Elan), it was replaced with a larger capacity unit (82.55 mm bore to give 1,557 cc). The engine's first appearance was in 1962 at the Nürburgring in a Lotus 23 driven by Jim Clark.
Keith Duckworth, from Cosworth, played an important part in tuning of the engine. Most of the development of the engine was done on the 997cc and 1,340cc bottom end, but in 1962 Ford released the 116E five bearing 1,498 cc engine and work centred on this. Colin Chapman's chance came when he commissioned Harry Mundy (a close friend and designer of the Coventry Climax engine and technical editor for Autocar) to design a twin-cam version of the Ford Kent engine. Colin Chapman had been wishing to build his own engines for Lotus, mainly because the Coventry Climax unit was so expensive. The history of the Cortina Lotus began in 1961.