From the February 2016 issue
While poltroons, charlatans, earnest amateurs, and fuzzy idealists vie for the presidency, in Southern Cali­fornia, Dan Gurney drafts proposals for a ­better internal-combustion engine. No, it’s not 1964, and we’re no longer stumping to send Mr. ­Gurney to Washington. But the 84-year-old non­pareil racer-cum-inventor refuses to retire. His latest work is the patented design of an internal-combustion engine intended for production vehicles.

With the pistons and the connecting rods rotated 90 degrees, the MC4S’s two cylinders drive individual crankshafts that rotate in opposite directions.
Called the MC4S, for moment-canceling four-stroke, it’s intended to be smoother and more reliable than the internal-combustion status quo. The design prioritizes durability, efficiency, and simplicity above power, and yet the engine still achieves the kind of perform­ance you’d expect coming from a guy with 51 major racing vic­tories. Gurney proposes that the MC4S engine could be used in everything from helicopters to cars; a motorcycle is the obvious first application, though. The breakthrough feature is in the bottom of Gurney’s two-cylinder, twin-crankshaft engine. Counterweights attached to the cranks cancel primary shaking forces as usual. Rotating the cranks in opposite directions eliminates the undesirable gyroscopic moment (rotating force) that occurs when the entire engine is rapidly rolled for cornering, henc...