Different types of coilovers

These are a very basic setup where the standard dampers of the car are converted with this spring set to be height adjustable by moving the preload on the spring. Spring preload is essentially how much the spring is compressed when installed on the car. A lot of OE suspension has huge amounts of preload hence the need for spring compressors to remove top mounts etc, With coilovers you generally run much less, and on some kits the recommended amount is to have no compression on the spring (or zero preload) where the spring is held in place but not compressed.

Most of the time these kits are a universal item meaning the springs are not matched to the weight of the car or the damping rate resulting in a terrible ride quality and limited options on height adjustment.

Generally speaking, an OE fit lowering spring is a better option than these if they are available for your car.

Read our article about Lowering Springs vs Coilovers

Next up comes the vehicle-specific coilovers with preload adjustment.

These are a replacement damper and matched spring suited to the individual car they are going on so are a much better option than sleeves. Generally, these re-use the standard top mount from the car's standard suspension so would not have any camber adjustment.

These allow you to raise and lower the car to your liking by adjusting the spring preload, compressing the spring will lift the car but can also give a slightly firmer ride. Many companies like TEIN and KW Suspension produce kits of this style which are set up and tested within a limited range of height adjustment to be able to be a very good ride and improved handling with a very simple setup process.

This coilover is ideal for people looking to improve the handling and looks of their car but not compromise on the daily usability of the car.

Pros:

• Simple to set up
• Improved handling
• Less to have to check during maintenance
• Normally use the car's OE top mount, making spares easier to source

Cons:

• Limited height adjustment
• Fixed damping
• Camber adjustment is often an optional extra

These coilover kits from brands like HSD and BC Racing are in our opinion the “best” option generally as they allow you to set the height of your car without affecting the spring preload or the ride quality of the suspension.

Kits like this also use a linear or straight spring of a standard size meaning you can fine-tune the spring rates much easier if you desire.

This style of coilover normally comes with a top mount and these can have camber adjustment depending on the car make/model.

Pros:

• Having a much larger range of height adjustment can lower the car an extreme amount if desired
• Uses a linear spring so can change spring rates easily
• Comes with top mounts and camber adjustment (where applicable)

Cons:

• Setup is slightly more involved in setting the preload and then the height and camber
• More to check when doing maintenance compared to adjustable height coilovers

Different types of dampers are used in some coilovers and this is where a lot of people get confused.

Twin-tube

Standard road cars use a twin-tube damper which has a tube of fluid and a tube of gas separate and these push against each other to control the motion of the spring. A lot of aftermarket coilovers have this style of damper and some have an adjustable version of this to fine-tune the car's ride. Generally, this is a single adjustment to change compression and rebound together.

This sort of setup is really good for a road-use car that would be a daily driver with some spirited use here and there and benefits from the oil having to flow through the chambers giving a slower rebound on the damper and a comfier ride over a slightly rougher surface like most UK roads.

Single tube

Kits like the HSD Monopro swap this to a single tube damper which runs at a higher pressure and is a firmer feeling unit. These are more suited to a slightly smoother surface for example a track day use but in most cases are adjustable and can be tuned to work well on the road as well on a softer setting.

These dampers allow for much larger internals to be used and a higher oil capacity which will cope with heat that is generated from hard driving much better. Also, Macpherson struts can be inverted which means that these become massively strong compared to conventional dampers. Inverted dampers are where the damper itself is upside down and mounted into a lower body, these have more contact points to absorb twisting and sideways loads.

Double wishbone cars do not need this as the wishbones take any loading not the coilover itself.

This style of damper tends to be used in adjustable coilovers where you can fine-tune the ride of the car. On inverted dampers this adjuster is at the bottom so may not be obvious in some images, similar to the twin tube this normally adjusts compression and rebound together.

For motorsport and track use, you may see cars using a remote reservoir coilover unit, like the KW V3 or BC ER series.

These are sometimes referred to as 3-way damper units and carry a much larger capacity of fluid. These also generally have adjustments for high and low-speed compression and rebound separately.

Remote reservoir dampers are not normally recommended for road cars as the damping on them when set for the optimum on track would be a little harsh on the road as the rebound /compression tends to be quite high on these. They also are more involved to set up and if you get the damping out of balance on them it can create a terrible ride and cause handling issues.

Pros:

• Incredible feedback through the car and vastly improved handling
• Can withstand much harder use
  
  

Cons:

• High cost
• Reservoirs need mounting to the body of the car
• Highly detailed setup

Depending on the kit you order you may get damping adjustment, generally most HSD and BC kits come with damper adjustment as do V2 KW and some Tein options but this would be a question related to each kit.

A simplified explanation of how these work is that the damper piston has an internal bypass valve and as you adjust the damper you open or close this.

This means that you can tune the ride quality on the car to behave how you wish in a very simple manner and keep the damper balanced in its motion.

Another question we are asked a lot is “Will I have camber adjustment?” This all depends on your car more than the coilover kit. Some cars have different types of suspension and this will dictate how your camber can be adjusted.