What Car Engines Rotate Counterclockwise?
by Derek WrayFactory car engines that rotate counterclockwise are mainly:
- pre-2000 Honda 4-cylinder engines
- rear-mounted Chevrolet Corvair engine from the 1960s
- Voisin and Citroen front-wheel drive French car engines from the 1920s and 1930s.
Before the year 2000, transversely mounted Honda 4-cylinder engines were predominately made to rotate counterclockwise. However, beginning with the K-series DOHC Honda engine in 2000, all North American-produced Honda car engines were created to rotate clockwise. The reason Honda made engines rotate counterclockwise -- which goes against the normal automotive engine-builder's standard -- was to simplify the internal mechanics of its front-wheel drive transmissions.
Counterclockwise Engines in Racing
The legendary, high performance genius Henry "Smokey" Smokey Yunick used to machine some of his racing engines to turn counterclockwise to gain an advantage on the racetrack. Yunick was an American mechanic and car designer associated with NASCAR, and he was twice voted NASCAR mechanic of the year. His teams included 50 of the most famous drivers in the sport, winning 57 races, including two championships in 1951 and 1953. In 1990, he was inducted into the Motorsports Hall of Fame.
"The idea of reverse rotation is, when you accelerate hard the weight comes to the left front and left rear, and pulls weight off of the right front. This more evenly distributes weight across the chassis, increases your lateral traction on the front and back end. You go faster.”
-Smokey Yunick, from his book: Best Damn Garage in Town
Factory Counterclockwise Rotating Engines
In the 1960s, Chevrolet's Corvair came with a flat-six rear-mounted engine, which rotated counterclockwise. In the late 1920s and 1930s, the French Luxury car Voisin had a 4.9L V12 front-wheel drive, which rotated counterclockwise, as did some of the early French Citroens.
Marine Engines
On some large V8 twin-engine boat applications, one engine turns clockwise and the other turns counterclockwise. Boat makers do this so that the propellers will spin opposite from one another, allowing the boat to go straight ahead instead of veering off to one side.
References
Writer Bio
Derek Wray is an ASE Master-certified automotive instructor and former professional technician. Wray graduated from Universal Technical Institute with a degree in automotive and diesel technology. He has received technical training from General Motors Corporation and is the author of an engine performance reference book for automotive students.
