What To Look For When Buying Coilovers

Categories: Ksport

KSports What to Look For When Buying Coilovers

The suspension of your vehicle is what ultimately determines how well it will handle. If your vehicle came from the factory with softer suspension, it will always handle poorly until the suspension is replaced with a performance setup such as coilovers. Old, worn out suspension also has a very negative effect on the handling and should be replaced, especially if used for any spirited driving where handling is key. There are many different coilover brands and types on the market, so picking the right one can be daunting. Here are four things you need to look for when buying coilovers.

What to look for when buying the best coilovers

Spring Rates

Springs are the integral part of your suspension set up. They control the vehicle’s ability to bounce, absorb bumps and create low body roll when loaded. Higher spring rates require more force to compress the spring, which reduces the amount of suspension travel. The body of our car moves when you accelerate, brake and turn. By reducing body movement you make handling more predictable and effectively spread the cornering load across all four tires better leading to better grip. Most aftermarket coilovers use significantly stiffer springs than OEM suspension, which improves handling and gives the driver more feel for the road and their car when performing spirited driving.

Spring rates are determined by the amount of pressure that it takes to compress the spring 1”. If your spring rate is 300 lbs per spring, that means the springs will compress 1” per 300 lb of load. If you add another 300 lbs to the springs, the spring will compress another inch to which the load on the spring is 600 lbs while the rate of the spring stays it’s constant 300 lbs per inch. Quick maths!

The ideal spring rate is different for each application. Drift, drag or street- what suspension you chose will drastically change how your car performs. Our Kontrol Pro Coilovers for example, use stiffer springs overall which massively improves handling in conjuction with our Monotube design damper. The selected coilover application changes internal shock valving to match the modified spring rate desired. For those who need even stiffer suspension, we offer a wide range of variations of spring rates for specific uses such as drifting, drag racing, rally, auto-cross and more.

What to look for when buying the best coilovers

Spring and Valving Adjustability

One of the many reasons anyone purchases a set of coilovers has commonly been to lower their car. The lower center of gravity will help reduce excessive body roll and improve performance. Having the adjustability for ride height, spring preload and damping are essential features of a high quality coilover. Adjusting your coilovers can help you fine tune how your vehicle handles and give it the perfect ride height for your application. The ability to replace the springs with stiffer springs is also an important feature as track cars need much higher spring rates than street cars to gain grip, improve handling and reduce body roll. If you swap to a stiffer or softer spring, it’s important to match your spring rate with your damping to avoid a bouncy ride which is ultimately detrimental to handling. Ride height, spring load and damping adjustment are all standard features on KSport Coilovers.

What to look for when buying the best coilovers

Top Mount

On top of the coilover is a mount that holds everything together and bolts the top of the coilover to the car. This mount is known as the “Top Mount” and between the mount and strut assembly are two different types of bushings, rubber or pillow-ball type. As you might expect, OE manufacturers use rubber bushings
because it deflects more and is a primary cause for the failure of suspension precision. The rubber you’ll find on most OEM struts is soft and allows a lot of energy deflection. A stiffer rubber mount improves longevity and reduces energy deflection. A pillow-ball bushing is a metallic spherical joint which r​ather than deflecting from the cornering forces like a conventional rubber bushing, pillow ball mounts do not move at all. This translates into a far more precise feel from the suspension and steering. The metal bearings will transmit far more vibrations from the road, which will make the vehicle less comfortable for daily use but essential for racing applications.

What to look for when buying the best coilovers

Monotube vs. Twin Tube Damper

Inside any coilover, there are two designs of dampers you will come across, monotube and twin tube.

The twin tube uses an inner and outer tube, twins if you will. The inner tube holds the piston shaft, valve and oil. The outer tube holds damper oil and nitrogen gas. How it works; When the suspension is compressed, the piston forces oil out of the inner tube by its valve and into the outer tube. When the piston moves back into position, the oil is sucked from the outer tube back to the inner. Most OEM suspension utilizes the twin tube damper set up because it allows for more suspension stroke and which improves ride quality.

Monotube dampers hold the gas and the shock in one tube, separating the liquid from the gas with a floating piston. The design pushes the damper piston through oil and pushes the oil through chambers through the valves in the piston itself. This design allows the gas to be compressed and react quicker, by compressing slowly over small bumps and more quickly through larger bumps. One incredibly important detail about the Monotube is its ability to be used either way up, unlike most twin tube dampers. Compared to the twin tube design, the Monotube holds more fluid, has better heat dissipation and improves the responsiveness of the damper.

For the best performance on the street or track, the Monotube design is a superior upgrade to the twin tube design.


Above all, it is important to buy coilovers from a knowledgeable and proven company who stands behind their products with a solid warranty and good customer service. Good spring rates, spring and valving adjustability, pillow ball top mounts and monotube are all great ways to spot a high quality coilover.

We hope this helped clarify all the options you have when it comes to choosing a coilover setup that is just right for you and your build. If you have any questions on exactly what you might need for your setup, please don’t hesitate to call our amazing customer service team today.