From the late 1950s he was responsible for all new models produced by Standard Triumph, starting with a facelift of the Standard Vanguard and going on to design models for Triumph such as the Herald, Spitfire, GT6, TR4, 2000, 1300, Stag, and Dolomite. He also created a number of prototypes which did not go into production, such as the Fury. The only Triumphs after 1960 that were not his work were the TR6 and the TR7, plus the Honda-based Acclaim.
In the 1960s, Michelotti designed a glass-reinforced plastic (GRP) cab for certain lorries made by Scammell, who had become part of Leyland in 1955. The cab was used for the Routeman, Handyman and Trunker models.
Michelotti also worked with the Dutch firm DAF, starting in 1963 with redesigning the ageing Daffodil 31 model into the Daffodil 32. The DAF 44 (1966) was a completely new design from his hand and he also helped form its derivatives, which culminated in the Volvo 66 (1975).
For other companies he designed the
- Lancia Aprilia Coupè (1949)
- Maserati SpyderTemplate:Clarify me
- Alpine A106 (1955)
- BMW 700 (1959)
- Prince Skyline Sport (1958)
- Armstrong Siddeley (a one off car based on the Sapphire 234 chassis for a Spanish client).
- Reliant Scimitar SS1 (1984) which was his last design to reach production, four years after his death.