economy was also improved to . The last USA models performed relatively poorly, owing to the compression ratios being reduced to allow the use of lower octane unleaded gasoline. The Mk III never sold in the numbers hoped for by Triumph, and was comprehensively beaten in the marketplace by the MGB. Triumph refused to release an official convertible version of the GT6 and, after poor sales, it was dropped from the Triumph range at the end of 1973, although a few cars were sold the following year. Diecast models Vitesse produced a 1/43 scale model of the Mk III in the 2000s. Spark produced a 1/43 scale model of the Mk II in 2010. References Further reading External links Triumph and Triumph GT6 Mk2 GT6 Rear-wheel-drive vehicles Sports cars 1970s cars Cars introduced in 1966 Automobiles with backbone chassis