XP-500 Free Piston Automobile

Media


Date

1956

Location

GM Tech Center
Warren, Michigan

I was there...

Tell us your story >

The General Motors XP-500 was the world’s first free piston automobile. It was an experimental vehicle built by the General Motors Research Laboratories that was completed and announced to the public in 1956 after 14 months of development. As it was finished just prior to the GM Technical Center dedication ceremony, it was featured at the exhibition day and on the national television broadcast that covered the event.

The XP-500 was similar in style to the gas-turbine powered Firebird II. It had a rounded all-glass roof like the Firebird II. The hood sloped down from the windshield to the low, horizontal grille opening and opened to reveal the engine compartment that housed the flat Hyprex engine.. The rear fenders had a wing-like quality and arched back over the wheels toward the tail of the vehicle.

The XP-500 was powered by the GM 4-4 Hyprex engine. The engine consisted of two parallel cylinders, each containing a set of two horizontally opposed pistons. An air-fuel charge fired between the pistons and the compressed air that was created by this action was piped into a turbine that helped power the drive train. This engine had an output of 250 horsepower.

Because of technical shortcomings and more promising research in other areas of alternative propulsion, General Motors halted further development on the free piston automobile within three years of the XP-500’s completion.

XP-500 Free Piston Automobile
XP-500 Free Piston Automobile



XP-500 at the Tech Center Dedication
XP-500 at the Tech Center Dedication






Tag Cloud

1897-1909 Creation  1910-1930 Acceleration  1931-1958 Emotion  1959-1981 Revolution  1982-1999 Globalization  2000-Future Transformation  AC Spark Plug  Advertising & Marketing  Alternative Fuels  Alternative Propulsion  Anniversaries  Autoshows  Behind the Scenes  Beyond North America  Board of Directors  Brands & Products  Buick  Cadillac  Celebrities  Chevrolet  Competitions  Concept Vehicles  Corporate Responsibility  DELCO  DELCO Electronics  Dealers & Distributors  Design  Design Centers  Detroit Diesel  Diversity  Education  Electromotive  Electronics  Emblems & Logos  Employees  Energy Conservation  Engineering  Enthusiasts  Environment & Energy  Eras  Executives  Finance  Firsts  Fisher Body  Former Divisions  Frigidaire  GMAC  GMC  GMOO - GM Overseas Operations  HUMMER  Headquarters  Holden  Hughes Electronics  I was there...  Innovation & Technology  Innovators  Joint Ventures  LaSalle  Manufacturing  Mergers & Acquisitions  Methods & Techniques  Motorama  Oakland  Oldsmobile  OnStar  Opel  Operating Units  Parade of Progress  People  Places  Plants  Pollution Control  Pontiac  Powertrain  Proving Grounds  Racing  Rally  Retirees  Saab  Safety  Sales & Service  Saturn  Shows & Events  Studios  Technical Centers  The Business  Trends  Vauxhall  World's Fairs