A coilover is an automobile suspension device. The name coilover is an abbreviation of "coil over shock absorber". [1]
A coilover is an automobile suspension device. The name coilover is an abbreviation of "coil over shock absorber". [1]
Coilovers are found on many vehicles, from RC cars to normal passenger cars, race cars and 4x4 vehicles. They are sometimes used as a factory suspension option on new cars. Coilovers are used in double wishbone suspension systems, [2] and are often a component of MacPherson struts. [3]
Two of the main types of coilovers are full coilovers and slip-on coilovers. Full coilovers are matched up with a shock absorber from the factory, while with slip-on coilovers, the dampers and springs are bought separately and then assembled. [4]
There are a large number of companies who make aftermarket coilovers for vehicles, many of which allow the customer to adjust various settings such as ride height and damping. Camber and caster angles can also be adjusted if the car's suspension allows, and if the coilovers are supplied with adjustable top mounts. [5] This high degree of adjustment is what gives coilovers an advantage over typical MacPherson struts.
Coilovers can be used to lower the vehicle's centre of gravity, and to increase the roll stiffness of the vehicle to reduce weight transfer when the vehicle changes direction. [6]
A coilover consists of a damper, with a coil spring encircling it. The damper and spring are assembled as a unit prior to installation, and are replaced as a unit when either of the sub-components fails.
Some coilovers are adjustable. Most, if not all, adjustable coilovers have variable ride height and preload, adjusted using a simple threaded spring perch similar to a nut. Alternatively, the damper's threaded body is matched to a threaded bottom mount which allows ride height adjustment without affecting bump travel. Most coilovers also have adjustable dampers, which are usually adjusted with an adjustment knob on top of the damper. Stiffness can be changed by switching the spring for one with a different spring rate [7] or by adjusting the stiffness of the damper.
Coilovers are made up of several components, including the damper, coil spring, bushing, bump stops, upper and lower mounts, various nuts and washers, threaded sleeves, and collars. [8]
The purpose of coilover springs is to prevent the chassis from bottoming out, support each individual wheel on the vehicle, and mitigate or reduce body roll when taking turns and cornering, particularly at higher speeds. The springs also help to reduce squatting when accelerating and diving when decelerating. They are often used to adjust the vehicle's ride height, which directly affects handling and comfort. [9]
Preload is the pressure exerted on a spring over the distance it is compressed. A higher preload means a stiffer spring and a lower preload results in a softer spring with more travel. This is true if the coilover uses progressive springs. On coilovers with linear springs preload has no effect on spring rate. More preload can increase grip when cornering, but too much preload can make a spring too stiff. In coilovers with adjustable spring seats, linear rate springs and no helper or tender springs, ride height must be adjusted through preload. This can present a problem for vehicles whose ride height needs to be lowered but whose springs are already stiff enough. [9]
A mono-tube coilover is a single piston and rod assembly in a damping case in which both compression and rebound occur. A larger mono-tube shock will be able to displace more hydraulic fluid, providing a more sensitive response to small suspension movements than twin-tube shocks.
A twin-tube coilover is more complex than a mono-tube assembly. Twin-tubes have an inner cylinder which moves up and down, and an outer cylinder which serves as a hydraulic reserve. This design allows for an increase in suspension stroke, which provides better ride quality and handling. [9]
Adjustable coilovers allow adjustment of the vehicle's suspension in four main areas:
Compression occurs when the piston inside the damper is moved inwards, increasing the pressure of the fluid in the chamber. Adjusting compression changes the motion of the vehicle's unsprung weight, modifying how quickly weight will shift downwards towards the wheel. Rebound is the result of the piston moving back after having been compressed, resulting in compression of the fluid once more. Adjustments made to rebound control the motion of the vehicle's sprung weight, changing how rapidly weight will be shifted away from the wheel. [9]
Nitrogen-charged struts can be used as a more stable alternative to coilovers since they do not unload or push off, increasing stability.
A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy which is then dissipated. Most shock absorbers are a form of dashpot.
Camber angle is one of the angles made by the wheels of a vehicle; specifically, it is the angle between the vertical axis of a wheel and the vertical axis of the vehicle when viewed from the front or rear. It is used in the creation of steering and suspension. If the top of the wheel is farther out than the bottom, it is called positive camber; if the bottom of the wheel is farther out than the top, it is called negative camber.
The MacPherson strut is a type of automotive suspension system that uses the top of a telescopic damper as the upper steering pivot. It is widely used in the front suspension of modern vehicles. The name comes from American automotive engineer Earle S. MacPherson, who invented and developed the design.
A strut is a structural component commonly found in engineering, aeronautics, architecture and anatomy. Struts generally work by resisting longitudinal compression, but they may also serve in tension.
A torsion bar suspension, also known as a torsion spring suspension, is any vehicle suspension that uses a torsion bar as its main weight-bearing spring. One end of a long metal bar is attached firmly to the vehicle chassis; the opposite end terminates in a lever, the torsion key, mounted perpendicular to the bar, that is attached to a suspension arm, a spindle, or the axle. Vertical motion of the wheel causes the bar to twist around its axis and is resisted by the bar's torsion resistance. The effective spring rate of the bar is determined by its length, cross section, shape, material, and manufacturing process.
Suspension is the system of tires, tire air, springs, shock absorbers and linkages that connects a vehicle to its wheels and allows relative motion between the two. Suspension systems must support both road holding/handling and ride quality, which are at odds with each other. The tuning of suspensions involves finding the right compromise. It is important for the suspension to keep the road wheel in contact with the road surface as much as possible, because all the road or ground forces acting on the vehicle do so through the contact patches of the tires. The suspension also protects the vehicle itself and any cargo or luggage from damage and wear. The design of front and rear suspension of a car may be different.
Automobile handling and vehicle handling are descriptions of the way a wheeled vehicle responds and reacts to the inputs of a driver, as well as how it moves along a track or road. It is commonly judged by how a vehicle performs particularly during cornering, acceleration, and braking as well as on the vehicle's directional stability when moving in steady state condition. Numerous factors affect handling
A double wishbone suspension is an independent suspension design for automobiles using two wishbone-shaped arms to locate the wheel. Each wishbone or arm has two mounting points to the chassis and one joint at the knuckle. The shock absorber and coil spring mount to the wishbones to control vertical movement. Double wishbone designs allow the engineer to carefully control the motion of the wheel throughout suspension travel, controlling such parameters as camber angle, caster angle, toe pattern, roll center height, scrub radius, scuff, and more.
The Chapman strut is a design of independent rear suspension used for light cars, particularly sports and racing cars. It takes its name from, and is best known for its use by, Colin Chapman of Lotus.
A swing axle is a simple type of independent suspension designed and patented by Edmund Rumpler in 1903. This was a revolutionary invention in automotive suspension, allowing driven (powered) wheels to follow uneven road surfaces independently, thus enabling the vehicle's wheels to maintain better road contact and holding; plus each wheel's reduced unsprung weight means their movements have less impact on the vehicle as a whole. The first automotive application was the Rumpler Tropfenwagen, later followed by the Mercedes 130H/150H/170H, the Standard Superior, the Volkswagen Beetle and its derivatives, the Chevrolet Corvair, and the roll-over prone M151 jeep amongst others.
An anti-roll bar is an automobile suspension part that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It links opposite front or rear wheels to a torsion spring using short lever arms for anchors. This increases the suspension's roll stiffness—its resistance to roll in turns.
In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles, and are used on virtually every automobile made. They bionically resemble the ball-and-socket joints found in most tetrapod animals.
A Corvette leaf spring is a type of independent suspension that utilizes a fiber-reinforced plastic (FRP) mono-leaf spring instead of more conventional coil springs. It is named after the Chevrolet Corvette, the American sports car for which it was originally developed and first utilized. A notable characteristic of this suspension configuration is the mounting of the mono-leaf spring such that it can serve as both ride spring and anti-roll spring. In contrast to many applications of leaf springs in automotive suspension designs, this type does not use the spring as a locating link. While this suspension type is most notably associated with several generations of the Chevrolet Corvette the design has been used in other production General Motors cars, as well as vehicles from Volvo Cars and Mercedes-Benz Sprinter van. Fiat produced cars with a similar configuration, using a multi-leaf steel spring in place of the FRP mono-leaf spring.
An active suspension is a type of automotive suspension that uses an onboard control system to control the vertical movement of the vehicle's wheels and axles relative to the chassis or vehicle frame, rather than the conventional passive suspension that relies solely on large springs to maintain static support and dampen the vertical wheel movements caused by the road surface. Active suspensions are divided into two classes: true active suspensions, and adaptive or semi-active suspensions. While semi-adaptive suspensions only vary shock absorber firmness to match changing road or dynamic conditions, active suspensions use some type of actuator to raise and lower the chassis independently at each wheel.
In motorsport, the racing setup, car setup or vehicle setup is the set of adjustments made to the vehicle in order to optimize its behaviour for specific conditions. Vehicle setups are variable for a variety of reasons, ranging from weather, driver/rider preference and race track characteristics. Contrary to common misperceptions, setup is not used to maximize the performance of the engine, but to optimize it for the track at which it is being used. For example, motorcycle racers frequently detune their engines to reduce performance and power output so as to ensure the bike accelerates in a predictable manner.
Bicycle suspension is the system, or systems, used to suspend the rider and bicycle in order to insulate them from the roughness of the terrain. Bicycle suspension is used primarily on mountain bikes, but is also common on hybrid bicycles.
Automotive suspension design is an aspect of automotive engineering, concerned with designing the suspension for cars and trucks. Suspension design for other vehicles is similar, though the process may not be as well established.
The twist-beam rear suspension is a type of automobile suspension based on a large H or C-shaped member. The front of the H attaches to the body via rubber bushings, and the rear of the H carries each stub-axle assembly, on each side of the car. The cross beam of the H holds the two trailing arms together, and provides the roll stiffness of the suspension, by twisting as the two trailing arms move vertically, relative to each other.
The Audi R8 LMS Cup was a one-make sports car racing series by Audi based in Asia. Audi R8 LMS Cup cars were based on the Audi R8 LMS (GT3).
Pull-rod suspension and push-rod suspension refer to a specialised type of automotive suspension system which is largely based on a double-wishbone system, incorporating elements of the commonly used MacPherson strut.
11. How to install coilovers on your vehicle ModifiedRides. 24th May 2021. Retrieved 19th March 2024.