The car I was thinking of... yeah... I remembered there was a FWD Chinese three-wheeler... turned out to be electric, so similar, but no cigar.
And the engine, without seeing it, sounds more like the Suzuki/Maruti 1.0. Which is a fantastically economical motor in its own right (I've done over 55 mpg in mixed traffic in a Maruti Alto) and relatively clean. The Alto can already do 60 mpg on the highway, so 65-70 mpg with a more streamlined body should be no sweat.
It's a cheap motor (built in India), and better than anything you can get from China for the same money.
Still, until there's a running production unit, it's all just talk...