This Crazy Six-Wheel Hatchback by Briggs & Stratton Was One of America's Fist Hybrids
Introduced in 1980, it could run 40 to 60 miles (64-96 km) on electric power and when its twin-cylinder kicked in, this six-wheeler could reach 68 mph (109 kph)
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To do that, the company's engineers equipped it with an air-cooled and carburated flat-twin engine rated at only 18 hp. This was the kind of unit that could be found in lawnmowers, and with a displacement of 694 cc (42 cubic inches), it was almost as small as the air filters of the era's underpowered V8s.
Not even the 46 series.. I think these are great engines, I have it in my tractor.