He was working on a freelance basis (including for Lotus) when Colin Chapman asked him to return full-time to design a car to compete in the Indianapolis 500. He produced the rear-engined Lotus 29 which, driven by Jim Clark, finished a close second at the 1963 Indianapolis 500 and the Lotus 34 for 1964 which, although starting from pole-position only completed 47 laps (out of 200) due to tyre and suspension problems. Terry later claimed that differences with Chapman meant the car had not been fully developed. He was also involved in the design of the Lotus 33 F1 car with which Clark won the Drivers' World Championship.