SUSPENSION 101
08-18-2001, 05:28 PM
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SUSPENSION 101
Okay Boys And Girls.....Class is about to begin. I was going wait until I finished doing a few more FAQ pages, but instead, I'm just gonna include this here so if anyone ever had any questions, they would be all set! Well, lots of good information here, so happy knowledge gaining!
Standard Suspension
Your Hyundai probably weighs in the neighborhood of 2500-3000 pounds. On a smooth straightaway it can easily travel at the legal speed limit, be it 55, 65, or even 75 mph. Unfortunately life is not a smooth straightaway. Instead it has cracks, dips, potholes, and bumps, as well turns and twists and curves. Your large pound mass of a Hyundai traveling at say 65, maintains contact with the Earth’s surface, by the scant size of the tires footprints…the total of 16 or so square inches where the rubber of 4 tires actually meets the road. We all know or can easily imagine the stresses and forces exerted on the tires considering the vehicles mass when those bumps and curves are encountered at speed. This brings us to suspension and shock absorbers, ride and handling, body roll, and over steer.
Very simply, suspension is a system of components, primarily springs, linkage, and shock absorbers, located between the vehicles frame and the axle designed to absorb energy. In other words, when a vehicle hits a bump, it’s the suspension that absorbs the energy created by the impact so it’s not transmitted violently through the tires into the body. Without a suspension system, every little imperfection in the roads surface would be translated into a violent force slamming into the body of the vehicle, resulting into discomfort for the passengers and damaging stress to the vehicle itself that results in those squeaks, rattles and cracks that we find in older cars. Obviously the tires are a critical component that must work well with the suspension. Without a suspension system, the upward motion of the tires when they hit a bump would launch the vehicle upward, resulting in loss of contact between the tires and the road. This of course, could cause loss of control at increased speeds.
Now for some definition lessons. Let’s begin with the “attitude” of the front wheels, including caster, camber, and toe in/toe out. Basically caster is the angle at which the wheel is attached to the vehicle. Consider a bicycle. The front wheel is not attached at the pivot directly beneath the frame, but rather at an angle. The front fork extends the front wheel out in front of the bike. The angle at which the wheel is affixed to the bike is the caster. All modern cars and trucks have caster. The upper ball joint and the lower ball joint, critical components of the suspension, essentially create the caster relative to their angle to the center of the wheel. Adjustment is made by moving the upper ball joint back, and the lower ball joint forward to place the spindle at 3 to 5 degrees of caster.
Camber is the side-to-side angle of the wheel. Imagine if you were flat on the ground looking straight ahead at the vertical angle of your cars front tire. Camber is measured relative to the ground, NOT relative to the chassis. Zero camber represents a perfectly vertical tire, which is considered optimum for braking and acceleration. Positive camber means the top of the tire is leaning away from the chassis. Negative camber means the top of the tire is leaning towards the chassis. When your car encounters bumps with both wheels usually go toward negative camber. The top of both the top loaded (weight bearing), and unloaded (non weight) bearing tires go toward the chassis. This is negative camber on both sides, even though one leans left and the other leans right.
Toe in/tow out is the difference in distance of the left to right measurements at the front and rear of the tire tread, on the same axle, measured at the center of the tread at spindle height. Toe in exists when the front measurement is less, while toe out exists when the rear measurement is less.
Now for some suspension components. The control arms simply provide a pivot point mounting the coil springs that put pressure on the control arms, which in turn hold the vehicle off the ground and suspend it. Spindles attach the upper and lower control arms to the wheel. This set up applies to both front corners, except in the case of vehicles with independent 4 wheel suspension, in which applies to all 4 corners.
The strut, a popular component on some model of vehicles, combines the shock absorber, spring, and upper control arm into one unit. All that is then required to complete a corner of the front suspension is a lower control arm, and a spindle, or in the case of front wheel cars…a steering knuckle. Struts like the MacPherson strut system work well on lighter vehicles, but are not beefy enough for heavier cars or trucks.
Stock suspension is what Hyundai considers to be the optimum ride height….ride and handling that will satisfy the largest number of potential buyers. The specs that direct the production of most factory vehicles are obviously not aimed at the enthusiasts. Peeps like us can modify the factory’s suspension by re-engineering it with quality aftermarket parts. As most of you know already, it’s possible to modify the stock suspension a great deal, and for the most part maintain the quality of ride and handling and still have a safe vehicle to drive. In order to do this, it’s best to understand what aftermarket suspension companies and products are available and what will work best for your situation.
Well, this has been Suspension 101…Getting To Know Your Suspension Components. Now that you are all experts on why your car turns, why you feel bumps more in one car over another, why your car goes over bumps easily, and what parts consist in your suspension buildup….you can go out and about in the world knowing more about your ride! *ha ha* ENJOY!!!! smile.gif
Standard Suspension
Your Hyundai probably weighs in the neighborhood of 2500-3000 pounds. On a smooth straightaway it can easily travel at the legal speed limit, be it 55, 65, or even 75 mph. Unfortunately life is not a smooth straightaway. Instead it has cracks, dips, potholes, and bumps, as well turns and twists and curves. Your large pound mass of a Hyundai traveling at say 65, maintains contact with the Earth’s surface, by the scant size of the tires footprints…the total of 16 or so square inches where the rubber of 4 tires actually meets the road. We all know or can easily imagine the stresses and forces exerted on the tires considering the vehicles mass when those bumps and curves are encountered at speed. This brings us to suspension and shock absorbers, ride and handling, body roll, and over steer.
Very simply, suspension is a system of components, primarily springs, linkage, and shock absorbers, located between the vehicles frame and the axle designed to absorb energy. In other words, when a vehicle hits a bump, it’s the suspension that absorbs the energy created by the impact so it’s not transmitted violently through the tires into the body. Without a suspension system, every little imperfection in the roads surface would be translated into a violent force slamming into the body of the vehicle, resulting into discomfort for the passengers and damaging stress to the vehicle itself that results in those squeaks, rattles and cracks that we find in older cars. Obviously the tires are a critical component that must work well with the suspension. Without a suspension system, the upward motion of the tires when they hit a bump would launch the vehicle upward, resulting in loss of contact between the tires and the road. This of course, could cause loss of control at increased speeds.
Now for some definition lessons. Let’s begin with the “attitude” of the front wheels, including caster, camber, and toe in/toe out. Basically caster is the angle at which the wheel is attached to the vehicle. Consider a bicycle. The front wheel is not attached at the pivot directly beneath the frame, but rather at an angle. The front fork extends the front wheel out in front of the bike. The angle at which the wheel is affixed to the bike is the caster. All modern cars and trucks have caster. The upper ball joint and the lower ball joint, critical components of the suspension, essentially create the caster relative to their angle to the center of the wheel. Adjustment is made by moving the upper ball joint back, and the lower ball joint forward to place the spindle at 3 to 5 degrees of caster.
Camber is the side-to-side angle of the wheel. Imagine if you were flat on the ground looking straight ahead at the vertical angle of your cars front tire. Camber is measured relative to the ground, NOT relative to the chassis. Zero camber represents a perfectly vertical tire, which is considered optimum for braking and acceleration. Positive camber means the top of the tire is leaning away from the chassis. Negative camber means the top of the tire is leaning towards the chassis. When your car encounters bumps with both wheels usually go toward negative camber. The top of both the top loaded (weight bearing), and unloaded (non weight) bearing tires go toward the chassis. This is negative camber on both sides, even though one leans left and the other leans right.
Toe in/tow out is the difference in distance of the left to right measurements at the front and rear of the tire tread, on the same axle, measured at the center of the tread at spindle height. Toe in exists when the front measurement is less, while toe out exists when the rear measurement is less.
Now for some suspension components. The control arms simply provide a pivot point mounting the coil springs that put pressure on the control arms, which in turn hold the vehicle off the ground and suspend it. Spindles attach the upper and lower control arms to the wheel. This set up applies to both front corners, except in the case of vehicles with independent 4 wheel suspension, in which applies to all 4 corners.
The strut, a popular component on some model of vehicles, combines the shock absorber, spring, and upper control arm into one unit. All that is then required to complete a corner of the front suspension is a lower control arm, and a spindle, or in the case of front wheel cars…a steering knuckle. Struts like the MacPherson strut system work well on lighter vehicles, but are not beefy enough for heavier cars or trucks.
Stock suspension is what Hyundai considers to be the optimum ride height….ride and handling that will satisfy the largest number of potential buyers. The specs that direct the production of most factory vehicles are obviously not aimed at the enthusiasts. Peeps like us can modify the factory’s suspension by re-engineering it with quality aftermarket parts. As most of you know already, it’s possible to modify the stock suspension a great deal, and for the most part maintain the quality of ride and handling and still have a safe vehicle to drive. In order to do this, it’s best to understand what aftermarket suspension companies and products are available and what will work best for your situation.
Well, this has been Suspension 101…Getting To Know Your Suspension Components. Now that you are all experts on why your car turns, why you feel bumps more in one car over another, why your car goes over bumps easily, and what parts consist in your suspension buildup….you can go out and about in the world knowing more about your ride! *ha ha* ENJOY!!!! smile.gif
