On most cars the stock suspension is a compromise between comfort and ideal handling. Car manufacturers design suspension to suit millions of people. It has to cope with a broken dirt road, the school run, and fully loaded motorway trips alike. The springs have a low stiffness rate to filter out bumps. That saves your back, but causes a lot of body roll. Likewise, the anti-roll bar sits in soft rubber bushings, which only slightly reduces body lean when cornering. The overall ride height is higher, which is practical for everyday use, but a car set this high leans clumsily and does not look aggressive or sporty.
Choosing suspension is one of the most important decisions when modifying a car. It affects not only how the car looks, but above all how it behaves in critical situations and in corners. Everyone is looking for something different – some want a budget solution, others uncompromising quality. Race-shop offers several ways to lower and improve a vehicle's suspension. The basic solution is to replace the stock springs with sport lowering springs. Then there is installing a complete sport suspension kit with a fixed, predetermined drop, or the more radical option – installing suspension that is adjustable in height and stiffness.
Sport springs
Installing sport springs is the basic tuning solution that adds stability and an aggressive look without having to replace the entire suspension. The stock spring is replaced by a sport spring in a plug & play fashion, while the damper itself and its mount remain stock. New bump stops and new top mounts are recommended during installation. Advantages of sport lowering springs:
- Improved handling: Sport springs are stiffer than stock ones. This limits body roll in corners. The car behaves more predictably thanks to them.
- Aesthetics: By lowering the ride height (typically by 20 to 40 mm) the car looks more aggressive and sporty. The gap between the tyre and the wheel arch is filled, which visually unifies the car's design and gives it an aggressive stance.
- Compromise on the road: Brands such as TEIN or MTS use progressive winding technology. This means that in normal driving over small bumps the springs are relatively comfortable, but when cornering hard, when they compress further, they stiffen up significantly.
- Price: This is the most affordable way to legally and safely modify your suspension. Most of these products come with a TÜV certificate for use on public roads.
Sport suspension with fixed lowering
A fixed suspension kit (springs + dampers with a shortened piston rod) is a plug & play solution where the complete suspension is replaced (usually except for the top damper mount). It represents the golden middle way. It is a pre-configured set of sport dampers with a shortened piston rod and lowering springs. Unlike adjustable suspension, here the manufacturer has already determined at the factory by how many millimetres the car will drop and how stiff it will be. The user does not interfere with the setup after installation. Just like the springs, most are TÜV approved for normal road use. Advantages of sport suspension with fixed lowering:
- More stable handling: Less body roll and better grip in corners.
- Aesthetics: Just as with sport springs, the car looks more aggressive.
- Plug & play installation: A direct replacement for the original suspension. Just swap the original dampers for sport ones, set the wheel alignment and enjoy sporty driving.
- Price/performance ratio: Fixed kits from TA-Technix or ST are only slightly more expensive than quality springs, but offer an incomparably better driving experience. At the same time they cost a fraction of what you would pay for premium adjustable suspension.
Adjustable suspension
Adjustable suspension, also known as coilovers, represents the absolute pinnacle of tuning and motorsport. Its main feature is a thread on the damper body that allows you to change the position of the lower damper mount and thus continuously regulate the vehicle's ride height. Stock suspension has a fixed spring seat and a knuckle bracket welded to the damper. The car's height is fixed by the length and stiffness of the spring. If you want to lower the car, you have to replace the whole spring or the complete damper. Adjustable suspension, on the other hand, has a thread on part of the body. On it sit adjustment collars that allow you to continuously move the damper mount in the knuckle or the spring (depending on the type of suspension). This lets you change the car's height over a range of several centimetres (e.g. from -30 mm to -80 mm) with millimetre precision. The benefit is a perfect setting of the distance between the body and the tyre, and therefore the ideal drop. Advantages of using adjustable suspension:
- Precise setup: Lets you set the suspension to the desired height. Besides height, some suspension kits also allow you to adjust stiffness, camber, caster and rebound speed.
- Multiple options: Adjustable suspension is the most widespread type of suspension upgrade. Different brands and different types let customers find the right solution for their use. Whether you are looking for just a basic height-adjustable kit such as TA-Technix, a compromise in the form of MTS, or the top of the market with Öhlins.
- Top-level construction: The range includes suspension with external reservoirs, which is the ideal solution for drift, rally or circuit racing. The larger oil volume ensures a longer service life and damping without stiffness changes due to overheating. Lightweight materials or uniball mounts are additional features of adjustable suspension.
- Weight distribution: Using adjustable dampers it is possible to "corner balance" the car. This means that by setting the correct height on each wheel you can influence the vehicle's weight distribution. This way you can achieve a 50:50 weight balance with a full tank and the driver behind the wheel.
Air suspension
Air suspension is the ideal choice for radically lowering a vehicle without losing comfort. It uses an air bag on all four dampers in combination with a compressor, which allows the vehicle to release and set the pressure, or rather a precise preset height. When driving, the bags are inflated by the compressor and the car rises to its normal or even a higher ride height. The whole system is controlled by a control unit that the user can configure, or the height can be set individually with a remote control or a switch connected to the suspension. All these kits are dedicated to a specific car model. Advantages of air suspension:
- Absolute control over height: The driver can raise or lower the car as needed
- Dynamic adaptation to load: Based on height sensors, air suspension can set the ride height by itself even when the vehicle is overloaded or unevenly loaded, so it always maintains the preset ride height.
- Progressive stiffness and controllability: An air bag has a progressive spring characteristic: the more it is compressed, the stiffer it gets. This means that when cornering harder the suspension naturally stiffens and minimises body roll. Many kits also allow adjustment of the dampers themselves (rebound/compression), so they can be tuned for a comfortable commute as well as weekend track driving.
- Protecting suspension components and the body: Conventional extremely lowered cars on stiff springs suffer from vibrations that are transmitted into the whole body (creaking plastics, material fatigue). The air bag acts as an insulator that absorbs high-frequency vibrations from the road, protecting not only your back but the car itself.
- Technology features: Many modern air suspension kits can be controlled remotely via Bluetooth, with various height and tilt settings and automatic modes.
Lift kits
In the segment of professional suspension modifications, lift kits are a technical solution designed to deliberately increase a vehicle's ride height, i.e. the exact opposite of air suspension. This type of modification is dominant mainly in off-road, expedition and utility vehicles, where high demands are placed on terrain capability and mechanical durability. Lift kits can be defined as comprehensive sets of components that change the geometry and ground clearance of the vehicle in order to maximise its utility off paved roads. In the world of lift kits there are two types of lift, or a combination of them.
Suspension lift: This is a technologically more demanding intervention that involves replacing the springs, dampers and often the control arms. This system raises not only the body but also the total suspension travel and axle articulation.
Body lift: This solution uses spacers between the vehicle's frame and its body. It makes room for larger tyres without affecting the suspension characteristics, while the vehicle's centre of gravity remains lower compared with a suspension lift.
Advantages of lift kits:
- Optimised off-road geometry: Installing a lift kit significantly improves the approach, departure and breakover angles. The vehicle is thus able to overcome steep terrain transitions and obstacles that, at stock height, would cause the underbody to contact the ground and lead to getting stuck or damaged.
- Fitting oversized tyres: Raising the wheel arches creates room to fit tyres with a larger diameter and an aggressive tread (AT and MT types). A larger wheel diameter is the only way to physically raise the lowest points of the vehicle, which are the differentials and axles.
- Improved static load capacity: Quality lift kits often use components with a higher load index. This is crucial for vehicles fitted with heavy expedition accessories such as heavy-duty bumpers, winches or roof tents, where the stock suspension shows signs of fatigue and excessive sag.
