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Dec 4, 2005 | 08:18 AM

#61 (permalink)

DriftingDJ

240LSX

Joined: May 2004

Posts: 2,456

Likes: 0

Acceleration
Accelerate with near full power in a front-wheel drive car and you'll quickly notice the resulting effect of rearward weight shift. The front tires will likely lose traction and spin – even on clean, dry pavement. By contrast, hard acceleration in rear-wheel drive cars increases the rear wheels' grip on good road surfaces because of the rearward weight shift.

Braking
Stopping ability is enhanced by the superior weight distribution of RWD. With the rear wheels carrying a greater percentage of the car's weight load than on a front-wheel drive car, they can apply more braking force to the road and help shorten stopping distances. Since RWD contributes to even tire wear, it is more likely that tires on a RWD car will have greater tread depth. Unless tires on a FWD car are rotated religiously, the front tires may become worn and less effective in braking.

Responsive Cornering
Near equal weight distribution helps give front and rear wheels more balanced traction. This balance gives neutral handling characteristics that make cornering maneuvers easier. Rear-wheel drive's more equal weight distribution also aids handling agility through a lower moment of inertia. FWD cars usually have higher moments of inertia, contributing to understeer and sluggishness in cornering. As a result, RWD cars feel more responsive, lighter, and more nimble.

Balanced Force Distribution
With FWD, both steering and propulsion forces tax the front tires' slip-resistance during cornering. That's part of the reason why FWD cars tend to understeer or plow forward, changing directions less quickly than the turning angle of the front wheels. Since RWD separates the tasks of cornering (front wheels) and propulsion (rear wheels), it more equally distributes the traction-threatening forces to all four wheels.

Torque Steering
Torque steering is a negative side-effect of FWD caused by the delivery of power to the wheels that steer the car. During acceleration in a curve or from a standstill, the force of torque steering can pose a hazard by changing the direction of the front wheels unless the driver is alert and can exert counteractive force on the steering wheel. RWD does not exhibit torque effect because the engine is isolated from the steering gear.

Longer Wheelbase
RWD allows a longer wheelbase and a more forward positioning of the front wheels. The longer wheelbase provides better handling while the forward position of the wheels reduces the possibility of the front spoiler scraping on dips.

No CV Joints
FWD cars have four CV (constant velocity) joints connecting the engine to the front wheels. In comparison, RWD cars use universal joints which wear out much slower than CV joints.

Summary

RWD pros:
Fore-aft weight distribution more balanced. Braking performance enhanced. Tire wear more even. Cornering easier, more responsive. Lighter than AWD configuration for better acceleration and cornering performance and better fuel-efficiency. Better hard acceleration performance on good surfaces than with FWD. Better cornering ability because steering and propulsion are applied at separate axles. Greater agility because of lower resistance to changes in direction (lower moment of inertia). Longer wheelbase for smoother ride. Absence of torque steering effect common with FWD. No CV joints to replace.

FWD pros:
Good traction during mild acceleration on slippery surfaces. Lighter weight helps fuel-efficiency. Interior room enhanced by lack of longitudinal driveshaft. Less expensive to manufacture.

AWD pros:
Traction enhanced on all road surfaces under all weather conditions. Faster acceleration "off the line" due to all wheels driving. Better road grip during

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