[vishwambar]

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.

[SergGT]

Factory car engines that rotate counterclockwise are mainly:

[r4king]

"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

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[Julia Darner]

Counterclockwise Engines in Racing more

[maxinedougherty]

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.

[agp]

Factory car engines that rotate counterclockwise are mainly:

[russ]

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.

[Vorlon]

Use of a reverse-rotation engine is even rarer among American car manufacturers than it is among the Japanese. However, in the U.S., one Chevrolet engine from the 1960s, called the "flat six", was made to spin in a counterclockwise direction. The model of vehicle was the Corvair, which was in production from 1960 to 1969. The engine was unique for American cars, for not only did it have a counterclockwise rotation, but the "flat six" was made from cast aluminium, had an air-cooled system and was mounted in the rear of the vehicle. With these unusual characteristics, the engine had more in common with a Volkswagen, Porsche or Lycoming aircraft than it did with other American vehicles. [links]

[hershel4merr]

The Corvair "flat six" could deliver as much as 140 horsepower and was one of the first engines to be turbocharged. As a result, the engine has frequently been used to power dune buggies and sports cars.

[Need2Revolt]

Engine rotation is determined by standing at the front of the engine and observing which way the flywheel spins. Most automobile engines spin to the right (clockwise), but a few do spin in the opposite direction, which is counterclockwise or anticlockwise. However, since the flywheel is not usually visible, other means might be necessary to determine direction of spin.

[chromicant]

Engines with reverse or counterclockwise rotation are rather rare in the automobile world. There is no scientific reason why a clockwise-rotating engine has become the norm. Most likely, this occurrence is just a result of standard convention. In regard to the use of a reverse-rotation engine, the main user is Honda. For many years, this Japanese car manufacturer has made a four-cylinder, reverse-rotation engine that was installed in the rear of their smaller vehicles. Beginning in 2000, Honda began to produce clockwise engines designed to replace the older ones, and by 2005, all American-made Honda engines were spinning in a clockwise direction.

[bosco]

Overall, there is no difference in the performance of the two engines. However, if you have to replace an engine, you cannot replace a counterclockwise version with a clockwise one, or vice-versa, unless you also change the transmission at the same time.

[alkor]

Twin engines are rare in automobiles and even when present, they do not usually necessitate the use of a reverse-rotation engine. However, when used side-by-side in vehicles such as power boats, aeroplanes or military vehicles, such as tanks, twin engines are made in equal sizes and rotate in opposite directions. In these cases, the opposing rotational spin becomes a balancing factor, which allows the vehicle to be driven forward with equal thrust and torque on each side.

[campsers123]

I think that on the small cars, the engine is ran right onto the axle, no differential or anything, so torque steer wouldn't be a problem. On regular cars, torque steer can be caused by different length axles, among other things. [links]

[DerrickEaton]

It redlines early because of it's 100 mm bore. fuckin huge ass pistons rotating don't make the engine as smooth as it could have. so Nissan threw on a compact balancer. the QR25DE engine is a waste of engineering and material as far as I'm concerned. I'm willing ot bet that people will be throwing in some SR20DETs in their new Vs very soon.

[stevesaxon]

My dad's Spec V is just like that. 1-2-3 gears are all smoke if you want them to be. Redlines WAY too early though.

[appamatto]

i found out; they actually use the reverse-rotation(motor spinning opposite direction from direction car is moving) in in small radio controlled cars that are 1/8th scale or smaller, while the larger cars (1/5) have them configured any way; awd and rwd. does this affect full-scale cars the same way?

[pc]

I think that on the small cars, the engine is ran right onto the axle, no differential or anything, so torque steer wouldn't be a problem. On regular cars, torque steer can be caused by different length axles, among other things.

[DevoJinx]

My dad's Spec V is just like that. 1-2-3 gears are all smoke if you want them to be. Redlines WAY too early though.