HISPANO-SUIZA WWI AERO ENGINE N.O.S. NEVER RUN

1918 V8 Wright Aeronautical Model H3 Hispano-Suiza aircraft engine, displacing 18.5L 1127 cubic inches, Bore: 140mm (5.51″) Stroke 150mm (5.9″). New old stock, from the estate of a Chicago aircraft pilot, famous for his cross country record flights and for his family who operated an airline in South America. He purchased this H3 Hispano to power a plane but never used it. I laid dormant in  a family owned furniture warehouse for half a century. It was acquired from the warehouse by a man who sold fabric covering for airplanes, who also never used it. Now nearly a 100 years old, the engine still has never been run and is in remarkable condition, like new. With the plan to use in a vintage mahogany speedboat, a marine conversion has recently been built and can be easily fitted. Price is $60,000 with recent marine conversion parts.

FURTHER COMMENTS: For the 1914 design date and their 100 year age, the Hispano V8s, are a very modern design and their creator, Marc Birkigt, may have been looking way ahead in time, as his engines run beautifully at much higher rpm than their aircraft contemporaries of a hundred years ago. Comparable engines of the time had very long strokes, such as the Liberty which had a Bore of 5″ and Stroke of 7 inches. With the nearly “square” bore stroke ratio in the Hispano they like to rev and run very nicely when fitted with higher compression ratio and run at higher rpm.  In WWI gasolines were commonly 40 to 60 octane. The H3 Hispano had a low, 5-1/2:1 Compression Ratio and were were rated conservatively at 325HP @ 1800 rpm. Today with 87 Octane pump gasolines and for use in vintage mahogany speedboats we have commonly fitted pistons of 7-1/2:1 CR and turned the engines 2400 to 2700 rpm. They become very spirited. In that trim, it’s easy to estimate that the H3s are making in excess of 500HP.  An old time aeronautical engineer, Charlie Grafflin, once said that the H3 Hispano had more horsepower per explosion than any engine he had ever seen.