Dan Gurney is known for many things. First and foremost, he’s a veteran race car driver who’s driven everything from the Ford GT40 at Le Mans to the Plymouth Superbird in NASCAR. When he won Le Mans with A.J. Foyt in 1967, he began a tradition that’s still practiced to this day in racing and other sports: the spraying of champagne on the podium. He’s also an inventor, having contributed the Gurney flap to racing and aviation, and the radical Alligator motorcycle to the two-wheeled world. Now, Gurney may be known for something else: a new internal combustion engine.
Gurney, along with his All American Racers racing team, recently patented an engine design called the “Moment-Cancelling 4-stroke.” It’s designed for motorcycle applications, but Gurney says it should also work in automobiles, aircraft, and boats. The goal was to create an internal combustion engine that was simple and compact, while also being smooth, powerful, efficient, and trouble-free.
Looking at the patent drawing, the engine appears to have two cylinders each with its own crankshaft. Those crankshafts are geared together, and if we understand correctly they turn in opposite directions. The motions of the pistons, connecting rods, and crank throws are mirrored so that much of the vibration is cancelled out. That’s how it works in theory, at least. Gurney says the first of five prototypes hasn’t run yet, though he does have simulation data that show test runs at various compression ratios. If the data are to be believed, the engine produces excellent power for an engine displacing 1.8 liters. Gurney says more cylinders could be added if the crankshafts were lengthened.
If it works, Gurney’s Moment-Cancelling engine could significantly reduce vibration in motorcycles. If it catches on, maybe we’ll see the design used in cars one day. What do you think of Gurney’s design? Check out the link below for a more detailed breakdown and tell us your thoughts in the comments.