How exactly can you tell if you have these? What exactly do they mean? I hear these terms alot, but don't know exactly what they mean or what causes them.

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86' IROC-Z
5.0L TPI
Spohn panhard bar and LCA's

 

I just had bad wheel hop when i hit 2nd in my 700r and it was a busted tranny mount.

 

BODYROLL-When you turn a corner, or swerve while driving the car wants to lean to the opposite side of the turn. The amount of bodyroll is described as how much the car leans to one side in this situation.
CAUSES-bad body mounts, soft or worn suspension(springs, bushings), or even worn, or underinflated tires.
WHEELHOP-While under hard acceleration, when the drive wheels bounce. This in turn will shake the fillings out of your teeth. It is hard on the whole drivtrain. Not a good situation at all. This is real common with leaf spring type suspensions.
CAUSES-worn rear springs, suspension geometry that is out of whack, wrong pinion angle
OVERSTEER-I get this confused with understeer to often so I will leave this alone.

Hope this helps


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Joshua Johnston
1991 Z-28
Flowmaster
K&N
305 / 5spd. (Temporary)

 

Just because I was bored I dug this up,,

Oversteer and understeer are two often misunderstood concepts related to the way a car handles. The following explanations and diagrams should clear up any confusion you may have.
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Oversteer is when the rear wheels are carving a larger arc than the front wheels or the intended line of the turn. Rear "slip angles" exceed those of the front tires. This is often described as a "loose" condition, as the car feels like it may swap ends, or be 'twitchy.'

This condition can be caused by "power oversteer", where you need to reduce power in order to bring the back end back into line.

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Understeer is when the front wheels are carving a larger arc than the rear wheels. This is often described as "push" or "pushing" - as the front end feels like it is plowing off of a corner.

Further acceleration only compounds the push, as weight shifts back to the rear drive wheels off of the front turning wheels, leading to a further lessening of the car's ability to turn in.</font>
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Understeer can be remedied by slight modulation in throttle to transfer weight forward to the front wheels, aiding their traction and ability to carve the turn.

Many cars are designed to have a tendency to understeer. If the driver gets uncomfortable and "lifts" off the gas, that will cause the front end to tighten the curve - a relatively safer, and more predictable condition.
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Wheel Hop

This is a simple (not necessarily interesting or technically correct) explanation of wheel hop:
The suspension and engine are connected to the rest of the car with flexible, rubber bushings and mounts. This flex kills vibrations, but it also produces a secondary, unwanted, oscillatory mechanical system. Normally, this system isn't acted on in such a way that it oscillates. When launching, the weight transfers to the rear of the car, reducing traction in the front. As the front tires break traction, the forces on the suspension and engine also change, setting them into motion. When the tires grab again, the forces change back the other way, now applied to a system already in motion. Now we have an oscillating force applied to an oscillating system, much like a hitting a paddleball. If you apply force to the paddle to match the natural frequency of the ball attached to the elastic string, you can keep that system going all day. With wheel hop, the motion of the system feeds back to the wheels, causing the oscillating force to sync up with it. This will also go on all day (until you reduce throttle or the transmission falls apart).
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Body Roll

What Is Body Roll?
Chances are, you've experienced the effects of body roll every time you're behind the wheel. It happens during almost every turn when one side of the car lifts, causing the entire vehicle to lean toward the outside of the turn.
The cause of body roll is simple physics: An object in motion tends to stay in motion until acted upon by an outside force. So in practical terms, as you drive ahead in a straight line, you're allowing a couple of thousand pounds of vehicle, fluids and passengers to build momentum in that straight line.
When you tell everything to change direction suddenly, through input at the steering wheel, the front tires may change direction thanks to the mechanical advantages of the steering system, but the momentum of the vehicle, fluids and passengers continues in the original direction. The tires are the only element capable of generating an outside force that can act against this momentum and change its direction.
At this point, one of two scenarios is most likely to occur. If enough momentum exists in the original direction, and the tires lack enough grip to act against the original forward energy, then the vehicle will slide out of the turn as the tires lose traction. However, if the tires have enough grip at the road surface, then instead of sliding, the vehicle's traction at the road surface will overwhelm the original forward momentum and act upon the original forces to induce a change of direction. Hence, a cornering maneuver.
But what happens to that energy? Even though we may have had enough grip to hang on through the turn, we know that the momentum of the vehicle mass will continue in the original direction. The result is a weight transfer toward the new outside edge of the vehicle-the same direction as the original forward momentum.
If enough energy is behind the weight transfer, then this energy will cause the outside suspension (in this case, the spring and strut assembly) to compress while the other side lifts and extends. An engineer type likes to describe this by saying that one side moves into jounce while the other moves into rebound. The rest of us call it lean or body roll.



Why Is Body Roll a Bad Thing?
We often hear that preventing body roll is "so important" that we must all rush out and buy this product or that product in order to prevent it. And many enthusiasts have consequently accepted that body roll is therefore bad. But what exactly does body roll do to negatively affect vehicle handling?
For starters, it disrupts the driver. This is probably the effect that most drivers can see and feel during their own driving experiences. And while this is not the most important negative effect of body roll, it is true that the car does not drive itself-no matter how many aftermarket parts you install. So keeping the driver settled, focused and able to concentrate on the task of driving is a foremost priority for spirited vehicle handling.
However, the most often misunderstood effect of body roll upon vehicle handling is the effect of body roll upon camber-and the effect of camber changes upon tire traction.
Put simply, the larger the contact patch of the tire, the more traction exists against the road surface, holding all else constant. But when the vehicle begins to lean or roll to one side, the tires are also forced to lean or roll to one side.
This can be described as a camber change in which the outside tire experiences increased positive camber (rolls to the outside edge of the tire) and the inside tire experiences increased negative camber (rolls to the inside edge of the tire.) So a tire that originally enjoyed a complete and flat contact patch prior to body roll must operate on only the tire edge during body roll.
The resulting loss of traction can allow the tires to more easily give way to the forces of weight transfer to the outside edge of the vehicle. When this happens, the vehicle slides sideways-which is generally a bad thing.



How to Prevent Body Roll
By definition, body roll only occurs when one side of the suspension is compressed (moves into jounce), while the other extends (moves into rebound). Therefore, we can limit body roll by making it harder for the driver-side and passenger-side suspensions to move in opposite directions.
One fairly obvious method to achieve this is through the use of stiffer springs. After all, a stiffer spring will compress less than a softer spring when subjected to an equal amount of force. And less compression of the suspension on the outside edge will result in less body roll.
However, stiffer springs require the use of stronger dampers (struts or shock absorbers) and have an immediate and substantial effect on ride quality. So, even though handling is improved, they may not be the easiest or most cost-effective way to achieve the objective of reducing body roll.
For many enthusiasts, the use of anti-roll bars-also known as anti-sway bars, roll bars, stabilizer bars or sway bars-provides a more cost-effective reduction in body roll with minimal negative impacts upon ride quality.

That should have your eyes thouroughly sore by now & you extremly bored but, more informed


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[This message has been edited by deadbird (edited July 10, 2001).]