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What material can an air suspension be made from? Do-it-yourself installation of air suspension on any car

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Thanks to air suspension, driving becomes easier and smoother when compared with shock absorbers. How does this element of the car work and does it have any disadvantages? Do-it-yourself air suspension: how to make it, what is the difference between installing the front and rear suspension.

The air suspension allows you to adjust the ride height semi-automatically or completely without the use of physical effort. We are talking about replacing springs, springs and torsion bars with pneumatic cylinders, in which compressed air pumped from the system acts as an elastic element. Despite all the advantages of this element, a do-it-yourself air suspension can only be created if you have basic car repair skills. The process is fraught with certain difficulties and a beginner clearly cannot cope with it.

The design of each air suspension consists of a receiver, a control unit, an air distribution system and a compressor. To improve driver comfort, the suspensions can be automatically or manually controlled.

  1. Automatic air suspension involves independently selecting the ride height electronically, taking into account factors such as acceleration, speed, and inclination. The focus in this case is on high aerodynamic performance. The center of gravity is reduced, so the car's controllability is significantly increased.
  2. Manual control requires the driver's initiative when choosing the height of the ground clearance relative to the road. Manual adjustment is also possible in relation to the stiffness of the suspension if its design involves the presence of shock absorber pneumatic struts.


Modifications

There are three modifications of air suspension:

  1. Single-circuit options are designed for installation on one axle and provide the same pressure in both cushions on it, since the compressor and cylinders are located on the same circuit.
  2. Double-circuit modifications are also installed on one axle, but in essence these are two single-circuit suspensions, thanks to which it is possible to adjust the height of the front and rear of the car relative to each other. The main disadvantage is the roll of the car, since there is a pressure difference between the two wheels that run along the outer radius.
  3. Four-circuit options are considered the best because they use four separate valves for each wheel, pressure sensors and a microcomputer for control. Consequently, the problem with roll is eliminated in this case, since the pillow steadily holds the required pressure.

Advantages and disadvantages of air suspension

Due to the positive properties of air suspension, there is a tendency to install it on both trailers and trucks, as well as passenger cars. The advantages of tuning a car with air suspension are represented by the following possibilities:

  1. Ride height control. This improves handling under all road conditions. In this case, the springs do not need to be changed to softer and longer ones or shorter and harder ones.
  2. Under heavy loads, sagging can be avoided, as the height and stiffness adjustments ensure consistent ride quality.
  3. Handling is significantly improved, and the air suspension compensates for the difference between hard and soft springs by adjusting the pressure.
  4. When driving on uneven roads, body vibrations are smoothed out.
  5. It is possible to install air suspension on any car.

The advantages are significant and there are many of them, however, it is worth knowing about the disadvantages:

  1. Poor resistance to road agents and frost, which significantly reduce the service life of the suspension.
  2. The level of maintainability tends to zero, so failure of one of the elements requires a complete replacement of the suspension.
  3. The cost is much higher compared to traditional shock absorbers.

Air suspension assembly

Since a do-it-yourself pneumatic device is only a subtype, installation is possible on an existing car suspension. The essence of the installation is to replace elastic elements with pneumatic cylinders, therefore, such a modernization scheme can be carried out on any machine. All that remains is to find out how to make an air suspension with your own hands and how to install it.


Necessary tools, materials and equipment

The equipment in this case is standard and every driver has it if he periodically encounters the need for repairs:

  • sealant;
  • hammer;
  • metal brush;
  • Bulgarian.

Do-it-yourself air suspension consists of the following components:

  • a set of racks, even if the ones currently installed are reliable;
  • receiver (you can make it for air suspension with your own hands and not buy it);
  • air suspension cushions;
  • compressor;
  • several different fittings and PVC pipes with a diameter of 6 and 8 mm;
  • two pairs of solenoid valves;
  • Any oil and moisture separator will do;
  • pressure gauge;
  • Control block.


Front suspension assembly

It is worth considering separately the technology for installing the rear and front suspension, since in the case of the latter the scheme is more complex.

  1. Knock the cap off the stand and clean off the paint layer using an angle grinder.
  2. Press the adapter onto the post and add spacers underneath to increase the softness.
  3. Select small diameter fittings or tubing and place them near the air holes in the adapter.
  4. Install the air spring onto the strut. The height of the bump stop should be calculated in advance, otherwise the spring may fail after the first strong impact on the road.
  5. Use caulk and a copper press washer to seal the connection.
  6. Secure the support bearing to the strut so that the rod does not rotate inside the shock absorber when the steering wheel is turned.
  7. Connect the air tube to the pillow socket.
  8. Now you can install the finished structure.


Rear suspension assembly

The step-by-step procedure for assembling the rear suspension is as follows:

  1. Trim the spring cup a little and remove the paint coating.
  2. To the end of the rack rod it is necessary to cut a thread for pneumatics.
  3. To seal, install a press washer and then put the air spring on the rod.
  4. To achieve particularly smooth movement, you can not install a bump stop, which will result in a strong lowering of the rear of the car.
  5. Press the air spring to the end of the shock absorber.
  6. Apply air supply.


Installing air suspension on a car

Before installing the air suspension yourself, remove the struts from the car. A beginner's skills will be enough in this case - just lift the car with a jack and follow the step-by-step process:

  1. Use existing holes to install the stand or make new ones if necessary.
  2. Remove the rubber bands and stretch the tubes to ensure air supply; then they must be secured in relation to the body using clamps.
  3. Attach the receiver to a special bracket near the gas tank.
  4. Lead the tubes from the airbags along the steering rods and lead them into the engine compartment. Make the wiring in two directions - to the receiver valve and the relief valve.
  5. Connect the pneumatics to the control unit toggle switches.

Functionality check

Be sure to check the system's functionality. After increasing the pressure to 8 atmospheres, check for leaks in the system by ear; there should be no hissing. Next, set the pressure in the system to 6 atmospheres for the rear suspensions and to 8 for the front ones. Do not rush when pumping air, otherwise there is a chance that the compressor will overfill the system. At the final stage, adjust the wheel alignment.

Suspension control

A control unit with 8 buttons is responsible for controlling the air suspension. Each button is responsible for a specific strut or shock absorbers in the complex. To receive data from each airbag, be sure to install the controller in the car interior. Based on the road situation, you can reduce or increase the air pressure in the airbag to reduce or, accordingly, increase ground clearance.

The corresponding button on the controller will allow you to disable the air suspension if necessary. The ride height indicators will immediately become average and the cushions will activate the standard spring shock absorbers.

Conclusion

Do-it-yourself air suspension is quite practical and stable in everyday use under different road conditions. The ride of the car will be soft and smooth, regardless of the quality and type of road surface. As for installation, a beginner is unlikely to be able to cope with all the stages of pre-manufacturing the air suspension on his own. Even if you have the relevant knowledge and experience, it is better to enlist the support of a partner and give preference only to reliable components.

  • Easy to install without assistance on almost any private or commercial vehicle: passenger car, SUV, minivan, pickup truck, van.
  • The dynamic characteristics of the vehicle are improved, the ride is smoother, the effects of overload are eliminated, compensation for the weight of the vehicle is achieved, and stable ground clearance of the vehicle is ensured.
  • The energy intensity of the factory suspension increases, since the pneumatic system works as compression buffers, which gives the air suspension structure progressive rigidity with a nonlinear elastic characteristic.
  • The service life of the front and rear standard suspension is increased, the possibility of damage to springs and springs is eliminated, and the vehicle's resistance to overloads is increased.
  • It becomes possible to increase the ground clearance, and the design of the air springs allows you to drive comfortably on broken roads.
  • Predictable behavior of the car in difficult road conditions is achieved; roll decreases when cornering, tire adhesion to the road improves; the braking system becomes more efficient; the position of the car's center of gravity is reduced, its directional stability is stabilized.

DIY air suspension 1600 1200 DIY air suspension

DIY pneumatic system for a car: design features

The air suspension is adjusted and controlled using a manual or automatic control system. The control unit is permanently connected to the vehicle's on-board network. When installing the air suspension yourself, the structural elements are installed in the following places:

  • Air suspension compressor - any suitable place on the car where there is no dirt and water: in the engine compartment under the hood, under the driver's seat, behind the seat or in another protected place; When installing, a special requirement is imposed on the compressor - it is installed strictly in a vertical position.
  • Receiver for air suspension - located in any convenient place for maintenance and control: under the body, in the engine compartment; it stores a supply of compressed air to maintain a given pressure in the system and supply air to the air cylinders.
  • Control keys - located on the front panel (dashboard) of the car; number of keys from 1 (for one axis) to 4 (for each wheel).
  • Pressure gauges for pressure control - mounted anywhere on the panel where there is a good view from the driver’s seat; can be hidden in the glove compartment along with the remote control keys.

How to install a car's air suspension with your own hands

When installing it yourself, you will have to replace the standard suspension elements with pneumatic elements. These are special air cylinders made of reinforced rubber with a bellows or sleeve type design. They are pumped with compressed air and constantly maintain increased pressure in the system. Pneumatic cylinders absorb road irregularities throughout their entire service life, softly absorb shocks, and reduce vibrations to acceptable values.

Before installing air suspension on a car with your own hands, you should decide on the type of pneumatic system:

  • Single-circuit - installed on one axis; The same pressure control is achieved in each air cylinder.
  • Double-circuit - is a combination of two single-circuit air suspensions, when the front and rear axles have their own pneumatics; provides independent regulation of ground clearance in the front and rear of the car.
  • Four-circuit is the most advanced option, when a computer, using four pressure sensors and check valves, automatically controls each air spring and, through air supply, completely levels out body roll.

How to make air suspension with your own hands

The air suspension developed in our company is installed instead of standard springs or serves as an additional elastic element to the spring leaves.

DIY air suspension
1600 1200 DIY air suspension Do-it-yourself air suspension - how to properly install an air suspension on a car, self-installation of a pneumatic system in a car

Select one of the air suspension kit mounting options and determine the optimal installation location:

  • For spring suspension - the location where the bump stop is attached.
  • For a spring suspension - at the place where the spring is installed, where the pneumatic element will be placed.
  • Overall and connection dimensions.
  • Allowable free space.
  • Working stroke of standard suspension.

It is also necessary to consider the purpose of the pillow:

  • To compensate for the load-carrying capacity, bellows-type pillows are installed.
  • For a comfortable ride, install a sleeve-type cushion.

Based on the design features of the suspension and the desired result, a suitable air spring is selected.

It is best to make brackets for attaching air bags yourself or order them from a specialist. For the manufacture of brackets, you can use carbon structural steel with a protective coating 6 mm thick or alloy steel of similar parameters.

Installation procedure and requirements

  • Buy a ready-made air suspension kit; The kit includes a compressor, a receiver, sensors for pressure control, an air suspension control unit, a pressure gauge, rubber hoses and pneumatic lines.
  • Raises the car using a car lift or jacks.
  • Remove the wheels where you plan to install the air suspension.
  • Remove the standard bump stops or suspension springs.
  • Install the brackets into the standard technological holes in the car body; They are easy to find by the rubber plugs.
  • It is highly not recommended to cut, weld or drill body parts and elements of the standard suspension!
  • Install the upper and lower bracket; place an air bag between them.
  • Under the mount, install flanges that are selected according to the diameter of the air spring and strut.
  • Mount the pneumatic lines - connecting tubes and compressor hoses. They are needed to ensure the supply of compressed air from the compressor to the receiver.
  • Lay the electrical wires to power the compressor from the on-board 12 V network and to power the control unit.

DIY air suspension
1600 1200 DIY air suspension Do-it-yourself air suspension - how to properly install an air suspension on a car, self-installation of a pneumatic system in a car

How to check serviceability and performance

After assembling the structural elements, it is necessary to check the operation and integrity of the system.

  • Pump air into the air springs and check the pressure.
  • Calibrate the pneumatic system and check the vehicle's ground clearance when it is fully loaded.
  • Pay attention to the uniform inflation of each air spring, the same position of the body above the floor level, and the absence of air leaks.
  • After installation is complete, re-adjust the wheel camber.

The A-Ride company offers a choice of pneumatic systems for cars of domestic and foreign production. We produce original components and sell ready-made kits for self-installation. We have the lowest prices and a one-year warranty. We invite you to take a look at our catalog and choose branded products for your car!

This device has been used in the automotive industry for about 60 years. Initially it was installed only on trucks and semi-trailers. But progress does not stand still, so air suspension is now installed on passenger cars. True, not for everything. But what about someone who wants to drive in comfort, but has not yet saved up money for a business class car? The answer is simple: install the air suspension yourself. We'll talk about how to do this today.

What is air suspension

In short, air suspension is a device that does not have spring shock absorbers. The driver can adjust the parameters of this device at his own discretion, and this can be done right on the go. When installing air suspension, standard springs, leaf springs and torsion bars are replaced with reinforced rubber air springs. The elastic element in air bags is air pumped by a special system, which includes the following parts:

  1. Compressor.
  2. Distribution valve system.
  3. Control block.
  4. Receiver.

Depending on the control method, air suspensions can be manual or automatic.

  • in manually controlled suspensions, the car owner independently sets the level of ground clearance (usually such devices are supplemented with pneumatic shock absorber struts, so the driver can manually set not only the ground clearance, but also the stiffness of the suspension);
  • in an automatic suspension, the electronic control unit itself will select the level of ground clearance, based on parameters such as speed, weight, lateral body roll, etc. If the adaptability of the automatic system is very high, then under certain conditions it can seriously lower the center of gravity of the car and repeatedly improve handling, especially when cornering;

According to their design, air suspensions are divided into:

  • single-circuit. In them, air bags with the same pressure are installed on one of the axles;
  • double-circuit. Here the pillows are also installed on the same axis, but the pressure in them may be different;
  • four-circuit. They are considered the best (and most expensive) because these suspensions use microcomputers, pressure sensors and a system of four separate valves, one for each wheel;

The most popular place to install a receiver and compressor in a passenger car is the trunk, or rather, the spare wheel niche. Of course, the spare tire will either have to be moved to another location or removed completely, compensating for its absence with tire sealant.

Is it worth installing air suspension?

In short: yes.

Now let's take a closer look.

What determines a comfortable ride without shaking and strong swaying of the car? Two parameters are important here: the weight of the car and the stiffness of the shock absorber springs. If the car is light and the springs are stiff, the driver is guaranteed to experience shaking. If the car is heavy and the springs are soft, it will roll like in the sea. This problem is aggravated by the fact that it is impossible in principle to match the stiffness of the springs and the mass of the car, since the mass is constantly changing, because the car has a different number of passengers, it can carry additional cargo, etc.

It is also impossible to change the stiffness of spring shock absorbers. Moreover, it falls over time (due to metal fatigue), and along with the rigidity, the vehicle’s ground clearance also decreases.

To regulate the stiffness of shock absorbers, an air suspension was created, the elements of which can adapt to the constantly changing parameters of the car, providing the driver with a comfortable ride in any conditions. Here are its advantages:

  • the vehicle's ground clearance and the rigidity of its struts are adjusted automatically;
  • the car becomes more resistant to overloads: in case of heavy load, the rigidity of the struts rises to the maximum, which avoids damage to other suspension parts;
  • improved handling: driving becomes smoother, car roll on turns is minimal;
  • when using a four-circuit automatic suspension, the longitudinal roll of the car also tends to a minimum, which makes the ride even more comfortable;

This device also has disadvantages:

  • Air shock absorbers cannot be repaired. If they fail, they can only be replaced;
  • the rubber of air springs is sensitive to cold and dirt (this will be discussed in more detail below);

Hydraulic suspensions should also be mentioned here. They perform the same function as pneumatic ones, but their elastic element is a special liquid. And the main difference between hydraulic suspensions is their increased reliability (and a very high price, which is unlikely to be affordable for the average car enthusiast). For example: the service life of an air suspension is on average 200 thousand km, while a hydraulic suspension can easily cover up to 400 thousand km.

From all of the above, a simple conclusion follows: air suspension is a good alternative to both stock springs and hydraulics with its exorbitant price.

Air suspension installation process

Before installing the air suspension, we should determine what we need for the job.

Tools and materials

Sequence of actions when installing air suspension

  • The car trunk opens and the spare wheel is removed from the niche;
  • There are plastic plugs on the side walls of the trunk that hold the mat in place. They are pryed off with a flat screwdriver and removed;
  • After this, the mat itself is removed. This gives access to the nuts of the racks and the holes that will be required for wiring;
  • the compressor is connected to the control unit and receiver as indicated in the instructions. After this, the assembled structure is installed in the spare wheel niche;
  • Then the wiring is connected to the receiver and compressor. Connection is carried out in strict accordance with the instructions on the wire labels;
  • the connected wires are assembled into one bundle, which is led out into the passenger compartment through an opening located under one of the rear seats;
  • then the harness is laid along one of the walls of the cabin, under the rugs and brought out into the engine compartment;
  • there the wires are connected to the battery, ground and to the fuse box as indicated in the operating instructions for the air suspension control unit;
  • Now one of the rear wheels is jacked up, after which, using a 22-mm open-end wrench, the 4 lower mounting nuts on the rear pillar are unscrewed;
  • using a 24mm socket, unscrew the upper mounting nut of the rear pillar through the hole in the trunk;
  • After unscrewing the top nut, the stand is removed. A similar operation is carried out with the second rear pillar. In place of the removed struts, pneumatic struts from the air suspension kit are installed;
  • to remove the front struts, on each of them, unscrew 4 fastening nuts with a 22 open-end wrench;
  • then the brake system hoses are disconnected and removed, the ABS sensor plug is manually disconnected (if the car has one);
  • the front struts are removed, the struts from the kit are installed in their place and securely screwed;
  • pneumatic lines are connected to the compressor, receiver and control unit in accordance with the instructions, after which the hoses are routed through the hole in the trunk;
  • the resulting air line is led into the engine compartment and connected;

Video: installing suspension on Mercedes Viano

Air suspension control

Any high-quality air suspension is equipped with a controller that is installed in the cabin. On its display, the driver can see both the pressure in the air bags and in the receiver. The car owner can choose pressure measurement units at his own discretion. The control units of high-quality four-circuit suspensions allow drivers to choose from several preset modes with a certain ground clearance (in particular, the Air-Lift air suspension, discussed above, has 8 such modes). The driver can select the desired mode with just one click of a button.

Moreover, over time, the driver will not need to click buttons at all, since the system will gradually “learn” the car, “get used” to its operating conditions, to the driving style of the car owner, and will itself maintain the optimal pressure in the air bags.

The air suspension is turned off from the same controller. When turned off, the system sets the average ground clearance, after which the air springs begin to work like regular spring shock absorbers.

Pneumatic shock absorbers are the main advantage of air suspensions. But they are also their weak point. This point is especially clear when the machine is operated in conditions close to extreme.

Air shock absorbers have 2 enemies: sand and cold.


Installing air suspension yourself is a task for advanced motorists who know exactly what they are doing. A novice who just got behind the wheel yesterday will clearly not be able to handle such a task. But experienced car enthusiasts also make mistakes. The most common are homemade products created on pillows ordered online from China. The quality of rubber in such “products”, as a rule, leaves much to be desired. And what management problems can lead to has already been written above.

But on our roads, this is simply suicide for a car. Besides, in such a car you can’t easily leave the city or go to the country, but many people want to be fashionable. To solve this problem, make the car’s suspension adjustable; pneumatics come to the rescue. With air suspension, you can raise or lower your car by simply pressing a button.

Let’s look at how to modify your car below, using the VAZ 2110 as an example.




The author decided to use available materials for homemade work. Mostly parts from gas cylinder equipment are used here. Well, as power elements you will need to buy four pillows with shock absorbers.

What is it made of?

Receiver for air suspension
The author made the receiver from a gas cylinder from a VAZ 2109. The choice fell on this particular cylinder because it can withstand high pressure (about 22 atmospheres) and also has a check valve, that is, nothing needs to be modified. And such cylinders also have a large volume, 45 liters, which will facilitate quick lifting of the car if necessary.



The disadvantages of such a receiver include its large weight and size. A smaller cylinder is suitable from Kamaz with a volume of 25 liters. But in this case, you will need to weld the fittings and make a check valve, although this option is best suited for the Classic.
The cylinder cost the author 2,500 rubles.

HBO valves
A total of 4 valves will be needed, two of them work for intake (front and rear), and two for discharge. If you choose high-quality valves, they will hold up to 25 atmospheres.

One valve costs about 350 rubles apiece.




About tubes
Initially, the author decided to use 6 mm oxygen tubes and fittings that were screwed into the HBO valves. But due to the heat, such hoses began to burst. Therefore, it is best to assemble everything at once on high-pressure PVC pipes; they are used in the brake system of trucks.
The author installed tubes with a diameter of 6 mm from the receiver to the intake valves, and 8 mm from the compressor to the receiver.
A meter of such a tube costs 35 rubles.






Which compressor should I install?
The first compressor that the author purchased was Berkut R17 (18A) (price 2950 rubles). In principle, it is quite sufficient for such purposes. For a reasonable price, it has good performance and resource. Later, the author decided to replace it with P20 (30A) (4950r), but other than the pumping speed, no special changes in operation were noticed.

If you decide to buy another compressor in this price range, remember that there are very few competitors to the above compressors.



Air suspension control panel
Since the system is dual-circuit, control occurs using only three toggle switches. The left toggle switch has three positions and controls the rear circuit. The right toggle switch also has three positions and controls the front circuit. Well, the middle toggle switch is needed to turn the compressor on and off.




Pressure gauge
A pressure gauge must be installed between the compressor and the receiver to monitor the pressure. There should also be a moisture separator here. Where to install the pressure gauge is up to everyone to decide for themselves.

It is advisable to look for nuts for supplying pneumatic tubes. Everything needs to be done using quick releases so that, if necessary, air can be pumped into the system at a tire shop or from the Compressor (in an emergency).

The pressure gauge costs 80 rubles apiece.








The total cost of the kit was 17,000 rubles.

Scheme
Initially, the author decided to make a double-circuit circuit. But due to problems on the front circuit, it was first made general. However, the pressure flowed from one airbag to another and the car began to roll on its side. As a result, the system began to consist of three circuits, and not two or four, as in the standard version.

As can be seen in the diagram, additional valves and toggle switches were installed.




After assembly, it turned out that the rear held pressure for a month, and the front for only two days, probably due to the heavy weight of the engine.
Later, the author modified the system control panel, and now it has become radio-controlled. But you can only control two circuits, since there are few buttons on the remote control.


Air suspension installation process
The shock absorber housing will need to be perfectly sized. Here you will need a turner. The diameter of the cushion is 45 mm, so that it fits tightly into the body, it is sharpened or adapter bushings are made. You will also need to make special sealing washers.





On the front boots you will need to remove the spring cups. Boots are the housings of the front struts, inside of which a cartridge (shock absorber) is placed.

The rear cups must first be lowered, and then, when the 15" wheel rests, cut off. There are special seals on the cushions in relation to the shock absorber rod.




Everyone knows how to install racks. To avoid making additional holes, the author used drainage holes. The rubber bands are removed from them and then oxygen tubes are inserted. Then they just need to be attached to the body with clamps.








The author placed the rear contour above the rear beam, and the hoses from the airbags were routed along the rear beam. The HBO valve, which is needed to bleed air, is placed on the gas tank bracket. The hose can be attached to the shock absorber with clamps, they are very flexible. There shouldn't be any problems with the rear circuit.






With the front circuit, everything is more complicated, since the hose passes through the entire car, but here the author was lucky, because his car is equipped with underbody lighting. The hose is easily attached with clamps to the tube, then to the stabilizer and goes to the front shield.








Hoses from the front airbags can be routed along the steering rods. Next, they are inserted into the engine compartment, a crosspiece is installed, hoses are routed, an air release valve and an LPG valve are installed.

We bring to your attention another project for installing air suspension. The object of this project was the Ford Focus.

Air suspension diagram

The air suspension is built according to a 4-circuit scheme, which allows you to control each air spring separately. Air supply/bleeding is carried out using solenoid valves. For the 4-circuit scheme, 8 pieces were needed, 2 pieces for each air spring.

Manufacturing of front air struts

To make air struts, we needed: a shock absorber strut, a support bearing, an upper strut support, an air spring, a flexible hose. For the air strut, the universal air spring Aero Sport, specially designed for MacPherson struts, was selected.

Additionally, turning parts were needed: a piece of pipe with an internal diameter equal to the diameter of the rack, upper and lower air spring mountings. The upper mount has a recess machined for the support bearing.



From the shock absorber strut, either with a hacksaw or carefully with a grinder, cut off the area for the spring.



Cut a ring from a piece of pipe. The height of this ring is chosen so that the air spring in a compressed state corresponds to the shock absorber in a compressed state.



We put on the ring, the lower mount of the air spring and weld it to the shock absorber strut.




We screw on the air spring, put on the bump stop (cut from a standard bump stop) and fasten the upper support of the air spring with countersunk bolts.



In the end, we got this pneumatic strut.


Installing front air struts

Installing air struts is practically no different from installing a conventional spring strut. To remove the spring shock absorber strut, unscrew 3 nuts from the upper strut support, one nut from the stabilizer bar and one bolt from the steering knuckle. Next, use zip ties to compress the spring and remove the strut from the fist.

We install the air spring in the reverse order, in this case it is necessary to position the hose leading to the air spring so that it does not touch or rub against the wheel.


Installing air bags on the rear suspension

For the rear suspension, there was plenty to choose from - for the Ford rear suspension, the appropriate sizes were Firestone 267c, Contitech 2500, SS-5 and RE-5, Air House 2 air springs. From all this variety, the choice was made in favor of inexpensive Contitech 2500 air springs

To remove the spring, use zip ties, after first removing the wheel and hanging the rear part.


To install the air spring, an upper support, a lower support and a disk for attaching the air spring to the lower arm were made.


The upper support is attached to the subframe with the same bolt that attaches the subframe to the body.


The lower support is installed inside the lever. From below, the air spring is bolted to the lower arm through a disk (which acts as a washer).


Air suspension layout

The main part of the air suspension elements is located in the trunk - this is the compressor, receiver, valves, pressure sensors.

For the Berkut R20 compressor, a shelf was made of 12 mm thick plywood in the left wing.


And a false floor was made for the valves. In addition to the valves, a spare tire, tools and a warning triangle were hidden there.


Covers are cut from sheets of plywood, coated with epoxy resin to protect them from moisture and covered with carpet. The receiver is located on the cover above the valves. The receiver had to be placed on blocks so that the excess pressure relief valve did not rest on the floor and it was possible to drain the condensate.


After assembling the entire system and covering it with carpet, the trunk began to look like this.


Digital air suspension pressure gauge

It was also decided to make a pressure gauge for the air suspension with our own hands. And although there are ready-made pressure gauges, for example, from Dakota Digital, I wanted to make my own for two main reasons: displaying pressure in bars and in the future making a fully automatic system with several programmable height levels.

The heart of the pressure gauge is the ATtiny26 microcontroller from Atmel, which includes an ADC with 11 inputs, of which 4 are used. It would also be possible to add a 5th sensor to the receiver, as in pressure gauges from Dakota Digital, but there is no great need for this. For the ADC of the microcontroller, an external reference voltage source is used on the TL431 chip, because the internal one turned out to be not very stable. Pressure sensors are powered by a voltage of 5 volts and have an output voltage ranging from 0.5 to 4.5 volts depending on the pressure. The information is displayed on a 2-line LCD display WH1602B from Winstar.


The pressure gauge is assembled on a breadboard and installed inside the car.



Air suspension price

The table below shows the list and cost (as of August 2011) of the parts required to install air suspension on a Ford Focus.

№ Name Qty Price, rub
1