General Motors Engineering Staff built and tested three small, lightweight urban cars with the numerical identity 512. These special purpose, two passenger cars are designed to provide short range personal transportation with some package carrying capability. Their top speed is limited at 30-45 mph. Separate roads or restricted driving areas would be required for these cars since they could not safely mix with full-sized cars and trucks. These small cars would help relieve urban traffic and parking problems. Their low power and energy requirements result in low vehicle emissions.
The 512 car series utilizes one basic body configuration as a test bed for different powerplants. Three have been tested to date: a conventional gasoline engine, a battery-electric, and a hybrid gasoline-electric. The gasoline powertrain consists of a 19.6 cu in., 2-cyl engine coupled with an automatic variable-ratio vee-belt transmission. The electric powerplant consists of a d-c series motor, solid-state controls, and a special lightweight 84 V lead-acid battery pack. The hybrid power system consists of an 11.7 cu in. gasoline engine coupled with a d-c series electric motor through an electromagnetic clutch. Electrical propulsion energy is provided by a 72 V lead-acid battery pack.