Car Steering Takes Bold New Turn
Some marketing experts see it as the safest, most significant driving development since disc brakes. Others, recalling such ephemeral revolutions as the rotary engine and the digital dashboard, aren’t buying the premise.
Californians will get to decide for themselves Tuesday when Honda showrooms start selling the 1988 Prelude 4WS--the first production car in America to offer optional four-wheel steering.
“We are confident it will be as accepted as, say, anti-lock brakes . . . as a growing thing until it’s a fairly significant option,” said Tom Elliott, senior vice president of operations for Gardena-based American Honda. In the coming model year, he said, 15% to 20% of Prelude production for the United States will be equipped with the option.
If Honda’s estimates hold firm, about 16,000 Americans will buy four-wheel-steering Preludes in a factory options package that includes alloy wheels and power door locks and adds $1,400 to the car’s sticker price of $16,500. In Japan, where the option has been available since spring, more than 80% of Honda Prelude buyers have purchased the handling option.
The selling point of the system is simple: Since the car’s rear wheels turn to follow the front ones, the results are tighter, flatter, quicker, and at high speeds, safer turns.
Call it stereo steering.
Some companies are betting a bundle on the system as the industry lead-in to cars of the ‘90s. Others are waiting to see if it will survive the model year.
Mazda, whose four-wheel steering sales are also soaring in Japan, plans to introduce the 4WS Mazda 626 to the United States in October. But its initial shipment will be only 200 4WS cars a month. “We believe that four-wheel steering is indeed the wave of the future,” said a spokesman, “What you’re seeing from us is a very cautious, almost tentative move toward that wave of the future.”
Nissan, which pioneered four-wheel steering in Japan in 1985, has sold 40,000 4WS Skylines (or 40% of the model run) since then. “But we have no immediate plans to bring it to the U.S.,” a spokesman said.
Mitsubishi, already in labor with the system’s second generation, will start offering a four-wheel steering, four-wheel drive, four-wheel independent suspension car to Japanese customers in October, 1988. “But as far as the U.S. market is concerned, that (4WS sales) is on hold,” a representative said.
Chrysler is studying four-wheel steering but has no production plans. General Motors has examined about 15 systems, has shortlisted three, but is producing none.
‘Not Convinced’
Ford has examined the concept, a company spokesman said, “but we’re not convinced we need to shove it into a Taurus just yet. A decade ago we’d jump into anything the competition came up with. But five years ago we started working way ahead, taking everything a little slower and a little easier.”
“We’re definitely approaching it with caution,” said Douglas Smith, former director of GM’s four-wheel steering program. “Because it’s another control system and that gets into the product-liability area. I think it (4WS) is going to happen. But I don’t think it’s going to be on every car nor will it be as widespread as the automatic (anti-lock) braking system.”
Despite its apparent novelty, four-wheel steering is as old as an all-terrain-but-mostly-mountainside vehicle that Mercedes built for the German military in 1935. A British race car experimented with the system in the ‘50s. And hook-and-ladder fire trucks--albeit aided by a tail-end driver and a second steering wheel--have been effectively demonstrating four-wheel steering since the Great Chicago Fire.
The problem with two-wheel steering is this: when a conventional car’s front wheels turn, a lateral force is generated at the front end, a yawing motion is created around the vehicle’s center of gravity, the fixed rear wheels are dragged around with the rest of the car and there’s a belated addition to the generation of lateral force. Plus the vehicle changes direction.
All of which makes for slower, wider turns with an uncomfortable, even dangerous shift of the balance of the moving vehicle when abruptly handled at higher speeds. That’s what makes cars spin into the boonies or go wheels up in the middle of the Harbor Freeway.
With four-wheel steering, when the rear wheels move in the same direction as the front wheels, the development of lateral force is simultaneous, yaw is reduced, and the car responds quicker to the turn. You can make a U-turn a u-turn.
The means: Honda has gone basic with a purely mechanical system. The standard rack-and-pinion steering unit is mated by a drive shaft coupled to a set of planetary gears housed at the rear. Turning the steering wheel moves the front wheels; the eccentric drive shaft turns the planetary gears that move tie rods turning the rear wheels.
Here’s the tricky part. Gentle steering adjustments (as in highway driving) change the rear wheel steer angle to a maximum 1.5 degrees in the same direction as the front wheels. That’s called “same steer.” But when the steering wheel is turned 240 degrees or more (as in parking or U-turns) the rear wheels steer in the opposite direction of the front wheels to a maximum 5.3 degrees. And that’s called “counter-steer,” the process by which the turning circle of a family sedan may be reduced from 35 feet to 31 feet.
And the results: Motoring magazines have come to a consensus. Four-wheel steering will never steer you wrong.
Changing Lanes
Reported Dennis Simanaitis of Newport Beach, executive editor of Road & Track, on the 4WS Nissan: “I could do the lane change 20-25 m.p.h. quicker . . . (4WS) made the abrupt maneuver absolutely without drama. Right now, same-steer is a functional and viable way to improve handling stability of a family car.”
Koji Okazaki writing in AutoWeek: “Up to about 75 mph, it is difficult to provoke the vehicle to do anything nasty while changing lanes.”
Yet there have been caveats among the critiques.
Will the average motorist pay an additional $1400 for a sedan that performs like a bumper car in supermarket parking lots? Or caster into a U-turn on a two-lane street with the aplomp of a London taxi? Although the high-speed, heavy-handling attributes of four-wheel steering are apparently undeniable, how many commuters are high-speed, heavy-handed drivers? Also, some experts believe the most effective, the least expensive four-wheel driving systems are yet to come. So why buy now?
Said Peter Brock of Rancho California, a former GM designer and automotive writer who recently hammered the Nissan 4WS Skyline at the Tochigi test track west of Tokyo: “I see four-wheel steering as a transient portion of development of the fully active suspension system . . . that’s four-wheel steering, ABS (Automatic Braking System), limited slip, automatic roll control and anti-squat controls.
Control System
“It will be very much like flying-by-wire (computer controlled) in a modern fighter plane, a control system that is so very much better and faster than anything you and I can do.”
“Think of it. We’ll be able to throw away springs and anti-roll bars to be replaced by a few microchips and an electronic system. And I think we’re only about five years away from that.”
To measure possible acceptance or rejection of four-wheel steering, The Times obtained a Honda Prelude 4SW and asked a cross section of motorists to evaluate the car.
Bill Drummond, a Newport Beach attorney, Richard Jenkins, a pool maintenance man from Burbank, and Kyle Bruss of Riverside were enthusiastic about the car. It rode flat, they said, on negative camber turns. Lots of front end push. Hard to break out.
But their opinions could be anticipated. Drummond drove a Lotus 23 as an amateur race car driver, Jenkins is a drag racer, and Bruss is a student and mechanic at the British School of Motor Racing at Riverside International Raceway.
So the Prelude was turned over to Wendy Walton, an assistant account executive for a Woodland Hills publicist; Carol Molina, a homemaker, and Sherman Oaks real estate salesman John Glance. None was told that the car was equipped with four-wheel steering.
None noticed anything unusual about the car’s steering or general handling.
Driving Enthusiast
The results did not surprise Elliott of Honda. That’s why the company decided to install four-wheel steering on its sporty, 120-m.p.h. Prelude, he said.
“The first interested consumers in the U.S. will be the driving enthusiast, the first people, traditionally, to spend money on a new development,” he explained. “We feel most of those people will buy it for improved highway handling.
“But after that, they’ll come to appreciate the low-speed maneuverability of the vehicle, which may very well become its most attractive feature.
