Rover later developed a derivative of the engine by fitting twin SU carburettors and a redesigned top end and marketed the revised specification vehicles as the 2000 TC. The 2000 TC was launched in March 1966 for export markets in North America and continental Europe. Limited availability of the redesigned induction manifold needed for the twin-carburetter engine was given as one reason for restricting the 2000 TC to overseas sales. The manufacturers also stated pointedly that the UK's recently introduced blanket 70 mph (113 km/h) speed limit would make the extra speed of the new car superfluous on the domestic market. Fortunately for performance-oriented UK buyers, supplies of the redesigned inlet manifold must have improved and the company relented in time for the London Motor Show in October 1966 when the 2000 TC became available for the UK market. The 2000 TC prototypes had run in the Rally of Great Britain as part of their test programme. It featured a bigger starter motor and tachometer as standard and was identifiable by "TC" initials on the bodywork. The power output of the 2000 TC engine was around . The standard specification engines continued in production in vehicles designated as 2000 SC models. These featured the original single SU.