If you'll search the classified ads in the back of a Popular Science Magazine you may still find a listing for Lindsey Publications' paperback '200-MPG Carburetors'.
There are a dozen designs or patent images for the 200 mpg vapor carbs.
The jist of the technology is that you push a car up to 35-mph,start the engine and engage the transmission,then motor along at 35-mph to achieve '200 mpg.'
There is no acceleration,or deceleration,different speeds available,hill-climbing,etc.,just flat level,constant-35-mph travel.
