The Mitsubishi HSR (Highly Sophisticated-transport Research) is a range of concept cars exhibited by Mitsubishi Motors through the late 1980s and 1990s. There were six distinct iterations of the vehicle released biannually to coincide with the Tokyo Motor Show, with each model after the original identified by a Roman numeral suffixed to the name.
The third concept car to bear the HSR name was powered by the 6A10 1.6 L V6, the world’s smallest mass-produced V6.
Source: Wikipedia