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Mitsubishi S-AWD Examined: Outlander PHEV Ice Journey


Forget everything you know about driving with AWD. That’s the first lesson I learned about Mitsubishi’s S-AWC system when the car company set me loose on a frozen skidpad to explore the system, its modes, and how everything worked.

The premise for the trip was a winter adventure — a drive on snowy rural Quebec back roads that were lined with ice, ruts, and (surprisingly) a liquor store’s worth of vineyards.

Winter Adventure Reduced to Ice Track Education

(Photo/Evan Williams)

But, winter isn’t what it used to be, even in the Great White North. So, while the temperatures were below freezing, there wasn’t much in the way of snow. Fortunately, Mitsubishi wasn’t relying on the MTQ (Quebec for DOT) doing a lousy job of clearing to make sure we could experience the AWD system. It had set up a course on the frozen surfaces at the International Center of Advanced Racing (ICAR).

ICAR races in both summer and winter. When it’s warm, the track hosts Canada’s NASCAR series, along with other events. In the winter, it’s an icy training ground for drivers — a perfect place to explore how an AWD system works.

Before I get to the driving, I need to explain the system and about how other AWD systems work. Then we can get to the fun part.

What Makes Mitsubishi’s S-AWC Different?

Mitsubishi Outlander PHEV Ice Experience
(Photo/Evan Williams)

Mitsubishi honed its All-Wheel Control (AWC) AWD system on the stages of the World Rally Championship and through the deserts of Dakar. The system combined computer control of yaw — how the vehicle rotates left and right around its center point — with an active center differential and the ABS system.

It became Super All-Wheel Control (S-AWC) on the 2007 Lancer Evolution, when it added the ability to transfer power left or right, not just forward and backward. It’s called torque vectoring, and it lets the system help the vehicle turn and not just accelerate in the snow.

Mitsubishi’s Secret Weapon: Sawase-San

Mitsubishi Outlander PHEV Ice Experience
Sawase behind the wheel of his creation; (photo/Mitsubishi)

The Outlander PHEV uses the same S-AWC name and comes with the same expertise behind it by way of Engineering Fellow Kaoru Sawase. Sawase has been with the automaker for about as long as it has sold cars in the U.S. He designed and developed the company’s electronically controlled center differential for the 1992 Galant. He also created the world’s first torque vectoring differential for the 1996 Lancer Evo IV.

Mitsubishi Outlander PHEV Means All-New AWD Hardware

Mitsubishi Outlander PHEV Ice Experience
(Photo/Evan Williams)

It has the same name, but the hardware underneath is completely different. The Outlander PHEV has twin-motor AWD. There is no center differential because the gas engine almost never powers the wheels. The front-mount motor drives the front tires, and the rear motor drives the ones in the back.

The technical effect of the system, electric motors, and front and rear differentials, is to give the engineers more freedom. There are no mechanical limitations to how little power the vehicle can send to one axle. The maximum is limited only by the motor itself.

Conventional AWD systems use mechanical or electronically controlled clutches in their center differentials. These clutches limit how much and how little torque can be sent front or rear.

Hyundai’s HTRAC system, for example, advertises it can send 100% of torque to the front, but only up to 50% to the rear. This can lead to front wheel spin in snowy, sandy, and muddy conditions that digs you into the terrain. With modern traction control, it can mean a system that won’t send any power to the ground at all as it tries to avoid wheel spin completely.

S-AWC adjusts power levels at each axle for traction when accelerating and for stability in corners, but most AWD systems can do that. Lateral torque vectoring on both axles sends power left or right for less side-to-side motion when accelerating in slippery conditions, which is much less common.

S-AWC also reduces sway in the wind by adding torque on the leeward side, and can add torque as needed to benefit low-traction cornering. Four-wheel brake control helps you stop, but it can also do a similar job to torque vectoring when you’re decelerating.

Set Loose on an Icy Test Track

Mitsubishi Outlander PHEV Ice Experience
(Photo/Evan Williams)

OK, time for the drive. We’re set up on a massive parking lot, coated in around a foot of ice. A tractor roughs up the surface every morning, leaving a thin layer almost like snow. Because even with the Yokohama BluEarth winter tires fitted, glare ice isn’t a surface where you’ll learn anything. Or go very far.

I started off in Normal drive mode. Normal is set up to offer torque distribution that uses less electricity when you’re going straight ahead and to intervene as though it thinks you’re on pavement.

The track is a large circle, and I can go around until I’ve learned what I need to learn or until I get car sick. In normal mode, I can make the circle at around 14 mph.

S-AWC Makes Slick-Road Driving Easier

Mitsubishi Outlander PHEV Ice Experience
(Photo/Evan Williams)

With a normal AWD system, I must constantly modulate the throttle and steering. A little more pedal when I think it can handle it, but less when the nose pushes out as the surface changes inch by inch. At the same time, it saws at the wheel to keep it in a circle.

In the Outlander PHEV, I have to stop moving the throttle and the steering. Hold them steady, and the computer figures out what to do. The nose will push out slightly but then immediately tuck back in as power is shifted to the outside wheel and the inside rear gets a touch of brake.

As long as I hold the wheel in the same position, the S-AWC system will try to give me the same result. It can’t break the laws of physics, but it sure seems to be bending them.

My next laps were in Snow mode. The system changes the equation because it knows there is less traction. It can’t lean on friction from the road the same way. It lowers the gain on the traction control and other systems but doesn’t turn them off.

The difference is immediately obvious. I can feel the system shuffling power and applying the brakes, but it is less aggressive and softer to respond. It’s like pretending there’s an egg under your foot, which is exactly how winter driving instructors will tell you to handle ice and snow.

I’m now getting closer to 20 mph in the same tight circle. The barely perceptible hand of the S-AWC system’s computers keeps me on course. As long as I keep the wheel turned and my foot in the same place, I could probably have a nap and wake up still going around in the same circle.

A Simulation of the Competition

Mitsubishi Outlander PHEV Ice Experience
Yokohama’s latest performance winter tire; (photo/Evan Williams)

But how much better is it than more conventional systems? Mitsubishi made us a special drive mode to simulate them.

The special mode switched the system from rear-biased power to 100% front bias. Power only went to the back when the fronts were slipping. It also turned off Active Yaw Control so that it couldn’t shift power left or right.

In this mode, it felt like the AWD compact crossovers I’m used to. Mash the gas, and the front spins before the rears finally show up. The front will slide wide, because the front tires are always getting power.

I can go at almost the same speeds, but I am sawing at the wheel and stabbing at the gas and even the brake. Instead of a smooth circle, I’m driving in a series of straight lines. Like an old low-res video game trying to render a curve.

How accurate was this mode? I tested a Subaru Crosstrek just before the event and a Hyundai Kona just after at my own makeshift version of this test. Their systems behaved almost exactly as Mitsubishi described. Maintaining the same circle in low traction conditions took significantly more work.

S-AWC Works When Driving, Not Just a Circle

Mitsubishi Outlander PHEV Ice Experience
(Photo/Evan Williams)

In the afternoon, Mitsubishi has the test vehicles on a longer course. This time, there are more twists and turns, as well as a slalom. The surface is slick from the sun starting to melt the snow, so the S-AWC system has to work even harder.

S-AWC is up to the task, making emergency lane changes and driving through the slalom with the same level of stability I would have expected on dry pavement, just at lower speeds. I can feel the difference between the Normal and Snow modes, with Snow much more effective at keeping me on track. This isn’t the typical snow mode on other vehicles, where the only change is a sluggish throttle.

The special “normal AWD” mode doesn’t like this surface at all. I have to cut my speeds in half, and even then, the Outlander is understeering and plowing. There is more body roll, and less stability, and I’m having to work a lot harder to keep going.

More Stable When the Roads Are Icy

Mitsubishi Outlander PHEV Ice Experience
(Photo/Mitsubishi)

Even from a stop, the difference is as glaring as the sun on the frozen field we’re using as a test track. Floor it in almost any AWD vehicle, and it will lurch left and right as the tires find traction and then lose it again.

Just below the point where traction control intervenes on basic AWD systems, you can feel the vehicle diving left and right as the friction levels change.

With S-AWC’s AYC, that feeling goes away. You don’t need to steer to keep going in a straight line because the computer knows what you want and reroutes torque to make sure that’s what the vehicle does.

The S-AWC system makes driving in snow and on ice easier. Making it easier also makes it safer. When the car does the work of making sure you’re on course for you, you don’t need the reflexes of a rally driver. You just need to keep driving.

If you spend enough time driving in deep snow, there’s one more benefit to the twin motor system’s lack of a center differential. It can’t overheat.

Any viscous-clutch center diff gets hot when the clutches are engaging and sending power to the rear. If there’s not much slip, it’s not a problem. If there’s a lot of slip, things get very hot. The differential can overheat and you’ll get a warning light telling you to stop driving until it cools. Or a mechanical failure.

System Works, but You Need to Use Your Feet

Mitsubishi Outlander PHEV Ice Experience
(Photo/Mitsubishi)

The one flaw in the S-AWC system is that it requires you to be accelerating or braking to have much of an effect. It can’t route power when the throttle is closed. So, like a boat, it steers best when you’re giving it some gas. It does work while braking and while coasting, but it works best with a little bit of gas. Just enough to maintain speed.

Intelligent Pedal, Mitsubishi’s one-pedal EV drive mode, made this even easier. It would apply the brakes automatically, helping to tuck the nose in and make sure the S-AWC system had something to work with. It will brake at up to 0.2G, enough to slow the vehicle without locking the tires.

Mitsubishi Outlander PHEV Ice Adventure

Mitsubishi Outlander PHEV Ice Experience
(Photo/Mitsubishi)

I know that as a driving enthusiast, electrification can be scary — worrying that modern vehicles will take away character, remove fun, and be less capable than what we’re used to.

The Mitsubishi Outlander PHEV’s Twin-Motor S-AWC system shows that you don’t need to worry. The companies that care about handling, even in mainstream crossovers, can deliver an experience that is not just up to what you’d expect from gas but actually better.

As Sawase-san told me at the event, electric systems require more work from engineers, but they give good engineers more freedom. For good engineers, he said, the systems are much better than mechanical. It’s engineering that you can feel in the Outlander PHEV — every time the road gets slick.



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