Lowering the height of your vehicle is a great way to improve handling. It lowers the center of gravity of the vehicle, thus reducing the amount of weight being shifted from side to side around turns. Lowering your vehicle just looks cool, so it’s popular for that reason as well.
Choosing stiffer springs can help keep your vehicle level, which improves handling. So with a lower center of gravity and more balanced suspension that doesn’t give around corners as much, you’ll be able to drive more comfortably at higher speeds.
Having the ability to easily adjust things like compressions (a.k.a. dampness), coil tension, and camber plates, is also a nice feature for those that want to customize their ride.
What Are Coilovers?
Coilovers are essentially aftermarket replacements for your OEM suspension, which is most probably a McPherson strut. But unlike a strut, a coilover is not a complete structural component. That is, if you removed a coilover, you could still drive, albeit with no suspension at all. Not a good idea, by the way, but it’s possible.
A strut actually forms part of the attachment to the wheel, so removing that and still driving would be a nice magic trick. I’m assuming you’re not David Blaine though, and neither am I, so unfortunately that’s not going to happen.
Coilover is actually short for ‘coil spring over strut’. If you have any current understanding of conventional suspension components, it’s pretty much what it sounds like. The strut aspect isn’t quite the same, as we mentioned above, but they do look similar.
What’s the Difference Between a Coilover and a Spring?
A spring by itself is not going to cut it. You would obviously need to attach it to something (like a coilspring or a strut) in order for it to work. So, let’s rephrase the question to make it more valid:
What difference would replacing my OEM spring with an aftermarket spring have compared to replacing my entire strut with a coilover?
Replacing your spring with a fancy new one will offer some new handling perks (not to mention being able to lower your vehicle that way), but not as much as replacing the whole part with a coilover. First, let’s talk about replacing the spring.
Replacing Your Current Springs for Shorter Ones
In order to provide the same level of support for the weight of your vehicle, a set of springs that is physically shorter than the ones you are replacing them with will have to have a higher kilogram to millimeter rating (that’s the standard measurement for springs). Consequently, it will make the ride of your vehicle a bit firmer.
Firmer suspension helps keep the car even, as we mentioned, which reduces what’s called ‘body roll’. It essentially increases stability, so at times when you’re accelerating, for example, the frame of your vehicle doesn’t rock back and then rock forth again when you ease up—as much.
Replacing your spring is certainly more cost effective than opting for a coilover, but the spring is not guaranteed to fit perfectly. If the fitting is off, this will affect handling and the overall feel of the suspension, so you should be careful when making a selection. Most likely, it will still be better than the OEM spring though. Your spring will not be adjustable like a coilover, but springs do come with either progressive or linear spring rates.
Non-Damper-Adjustable Coilovers vs Fully Adjustable
As a cheaper option, non-adjustable coilovers are available. They still allow you to adjust the height of the vehicle, but not the compression of the damper (the cylinder and piston part of the shock absorber) or stiffness. They’re still good for lowering your car and likely improving the handling of your vehicle, and they’re often not far off in price compared to brand new standard struts.
Fully adjustable coilovers allow rebound, spring pre-load, camber, vehicle height, and damping to all be adjusted. Some models are quite light, which improves handling. But lighter models are typically more expensive.
Coilovers can also have their springs changed for even more customizability. Those specifically designed for off-road vehicles come with remote canisters for increasing the capacity of the fluid for cooling.
There are two main types of coilovers in terms of how they can be adjusted. One way is to adjust the height by way of the spring, which is actually not preferable because it changes the spring’s pre-load settings. Consequently, the vehicle will likely handle differently. The other type has thread on the shock body itself, allowing you to adjust the height without interfering with the springs. The base mount is adjusted instead by way of C Spanners. This is definitely preferable, but if you don’t plan on adjusting your vehicle’s height often, the other type should be sufficient.
To recap, spring replacements are cheaper, but aren’t nearly as adjustable or as convenient. They don’t offer the same freedom to curtail your vehicle’s suspension system along with its height. Coilovers might cost more, but for performance driving, they’re certainly preferable—especially fully adjustable coilovers.