How many of you out there have bought into the myth that front-wheel-drive is safer than rear-wheel-drive, but not as safe as all-wheel-drive or 4X4? We’ll wait while you think about it – take your time, we’re not going anywhere!
Okay, it looks like we have an answer about 90 or more percent of you have bought into Detroit’s marketing plan to get you into a front-drive car. Well, we’re sorry to have to inform you of a little-known – well, at least little-publicized fact – front-wheel-drive vehicles are not safer than rear-wheel-drive models. In some cases, they are downright more dangerous?
How Is It Possible?
To figure out how this is possible we have to first turn back the DVD player of life to the early 1970s when domestic model cars with standard pattern layout – front-engine/rear-drive – were bordering on the truly frightening size of 22 feet long. Now, that’s a big car, isn’t it? You’d need a humongous engine to power said machine, wouldn’t you? General Motors settled on the 7.4-liter 455-cubic-inch V-8 that put out about 290 horsepower in street trim but which could easily be tweaked to 400-plus. Of course, gas mileage was dismal and, if anything, the handling was worse. However, if you asked an answer of an Eldorado, at the time, one of the first GM front-drive models, you would have been told that front-drive was the next best thing to slice bread.
Especially in snow weather, these drivers pointed out that their vehicles could get out of snowdrifts more easily the rear-wheel-drive cars and that front-drive vehicles (about 5,000 pounds at the time) tended to hold the road better on long snowy stretches of straight road.
All Of This Is True But…
All of this is true – when you’re talking about 5,000 pound cars, of course, with big engines – but here’s something interesting that these drivers managed to overlook and that was when they hit the gas the front wheels spun up to speed and the vehicle began to pull to the right. This is called torque steer and it’s a function of front-drive cars (the 36 Cord had it in abandon and the accidents it caused forced the company out of business). The power hits the right wheel first and the vehicle slews to the right.
That’s not something that was mentioned in too many ads, at the time, either.
And then there was the ever-present trailing throttle oversteer. It seems that on decreasing radius curves, such as off-ramps, if you suddenly pull your foot off the gas, the front-end had this habit of turning in on itself to the right, while the left rear, now lightened up by the added torque and weight over the front right driving wheel, began to come around so that the vehicle tried, literally, to swap ends. It was a function of the technology of the time.
(Much of these problems has been dialed out into today’s front-drive vehicle but it is still there is you look for it.)
Weight Distribution Problem
Finally, there was the problem of weight. With a front-engine/rear-drive vehicle the weight distribution tended to be 50/50 which made the handling – albeit number because of the era – still rather neutral. Now, picture moving 69 percent of the vehicle’s weight over the driving wheels. It was creating a front-heavy vehicle or to put it in another perspective, imagine a knife that isn’t balance with all of the weight in the blade. Now, imagine hurling that knife at a target. Will it hit the target? Yes, of course, it will. Will it be at an angle to stick into the the target? Probably not because even though the weight is from the haft forward, the way the knife would spin through the air would mean it would likely hit the target on the side, although, to be truthful, you would still have your greatest chance of hitting the target and scoring a bullseye with this configuration.
The other part of this equation is simply this: you would not be able to deflect the knife from its line of flight because it was front-heavy. It’s like throwing an engineer’s plumb line and weight and trying to move them from their lien – it’s not likely to happen.
Car’s Present A Problem
Scale this up to a vehicle and you can see that no matter what happens and how you drive – unless you are taking it slowly – there’s only one possibility in front-drive and snow and ice, if you hit your brakes. Your car is going into a skid and you won’t steer out of it, unless you get off the gas right away and let the vehicle coast down to a stop. It’s all a function of the physics of car design.
What isn’t a function of the physics of this type of car design, but is a result of it is that engineers could quickly see the packaging advantages of front-drive.
The advantages were:
Designing smaller vehicles, but keeping the interior size the same
Designing smaller, more fuel-efficient vehicles that could still carry five to six
Designing smaller vehicles that were truly small and yet offered lots of interior space
Some of this may sound redundant but it isn’t. Packaging is an important practice in the car business and if you can shave feet off your car as well as pounds and pounds of excess weight, then you have a more efficient vehicle that can be driven by a smaller engine.
This combination achieves the industry’s obsession with keeping interior size the same but shrinking the package.
With front drive you can literally adjust the wheelbase and position to your needs – the wheels can actually be outside the bearing lines of the vehicle – and you can still keep room for four or five people and their packages and luggage.
Front-drive, then, is a packaging editor’s utopia, but a chassis or powertrain engineer’s worst nightmare.
Refinement Takes Years
Beginning with the VW Golf (Rabbit at the time) and the Plymouth Horizon, Detroit’s engineers saw you could design small cars that performed reasonably well, were able to have standard four-cylinder powerplant and could still carry five in comfort.
From a performance standpoint, though, they left a lot to be desired and it has taken nearly 40 years of continuous refinement to make the front-drive vehicle the standard that it is today.
Don’t let anyone tell you, though, that front-drive is ultimately a safety feature, because it isn’t. It’s a packaging designers plaything and while it may have had some early design success as a safety feature the long and the short of it is that front-drive is why Detroit has been able to keep five- and six-passenger vehicles viable for so long. It’s a packager’s delight.
Having spent more than 30 years as the dean of Boston’s newspaper auto columnists, I have more than a fair to middling knowledge of cars and their problems plus how to drive; how to buy; and how to use the system. Interestingly, I not only spent many years as an automotive writer, but I also spent nearly seven years selling retail either as the Internet Sales Manager for a major Boston area Honda preowned store, as well as serving as a retail salesman on the floor of a couple of domestic dealerships. I can write authoritatively about this topic because I have lived it since my Mom ran a brake rebuilding/relining shop in Boston in the 1950s when I was a kid and I had to go into the office on Saturdays as that was how she brought us up. I have worked on engines and I did the obligatory gas-pump jockey bit as a teen. In other words, I’ve been around cars and the industry for a long time.