40 years ago in a gas price crisis a company offered a kit that disabled half of a V-8 engine for all the obvious reasons. Common Ford and GM engine kits were advertised to be in stock and installation was supposed to be somewhat simple. The front and rear piston on one back and the center 2 piston on the opposite side would be replaced with dummy pistons with holes in the top. The rockers on disabled cylinders were removed and a spring loaded cap replaced them and the exhaust valves were left out. half the carburetor no longer operated due to lack of vacuum. I never saw an engine with such a kit installed and never had much confidence that installing it would ever be worth the cost. I seem to recall a Transmaro in the ad and wonder just how a 175 cubic inch 4 cylinder would get that car out of a light ahead of a bicycle.
While that kit was advertised in auto magazine a “Solar Clothes Dryer” was offered in Better Housekeeping. A friend bought that drier for about $50. It was 50 feet of cord, 2 eye bolts and a sack of clothes pins.