One thing we all share is an intense love for 4 cylinder and high tech performance vehicles. But while some of us live for the adrenalin rush that straight-line dueling provides, others crave the cocaine shot in the arm of drifting. Here we take a look at the different ways you can set your cars suspension, and what the outcomes will be.
Ok so once you have found your perfect ride and it is sitting in your driveway or garage, you have to consider what type of suspension you want. Weighing up the options will probably reveal that your car can’t be too extreme if you want it to be street driven daily driver. But there are measures you can take which will make your car do what you want it to do.
If you are planning on building something with a purpose, such as a drift car, there are a few fundamental things you will need to remember. In general soft springs on the driven wheels will allow the tyre to provide more traction. The stiffer the sway bar, the less grip on that end of the vehicle. For example if you had a stiff front sway bar, but a soft rear end, you would have less front grip and more rear grip.
With rally applications wheel travel is important, but for most other applications give yourself just enough to ensure that the bump stops are not being hit when working. Suspension travel is essential in rally because the more compliant the suspension, the more tyre contact with the road. When a hole or bump is hit the softer suspension will drop down into the hole so the tyres are still touching the road. Stiff springs will hold the tyres off the ground in those situations because they are too tight.
Drag Car – Straight Shooter
First of all it is important to understand what drag racing is all about. Drag racing is a contest of acceleration. The winner is the quickest car over the quarter mile not the fastest. Sure top speed is important, but it is a byproduct of acceleration. This being the case it is supremely important to have a great take off at the beginning of the run. Achieving this is easier said than done, and the suspension set up is one of the more fascinating aspects of drag racing.
There are two important things to consider when setting up a car in an attempt to generate a fast acceleration time down the quarter mile. Both of them revolve around generating and maintaining as much traction as physically possible. The first of these two is to bolt on a fat set of grippy tyres. Whether they be a set of slicks, or a high traction road wheels, they are a great way to increase your vehicles ‘hook up’ potential to Don Juan status. Dialing out any negative camber at the rear will guarantee that the bigger tyres will be sitting flat on the take off pad, allowing them to work to their optimum design.
The second important consideration is weight transfer. There are many different types of car chassis and suspension lay-outs, but weight transfer is an important consideration in all. Transferring weight to the rear wheels is easier than to the front wheels and so we will concentrate on this for the moment.
Most drag cars will have more than enough power to overcome traction, particularly in the lower gears. Weight being exerted on the tyres is what is needed to allow the car to put the engine’s power to good effect. The goal of a drag racing suspension set up is to have the chassis transferring as much weight as possible to the tyres which are driving the car forward.
This means the rear suspension to be as soft as possible, so the tyres can be pressed flat against the bitumen for maximum effect. This give will also allow the car to squat, so that the weight of the front end is exerting itself onto the rear tyres. You can’t just go out and buy the softest springs you can find though. You need a compromise between soft springs and making sure the car does not bottom out too harshly.
Another tactic is to put a hard sway bar on the front of the car, (or in a FWD situation, on the rear). This will help the car stay as flat as possible and help to apply weight to the desired area with a stout chassis.
Drift Car – Drift Pig
Essentially drifting can be described as the art of sliding a car through a series of corners in a controlled fashion. Any car can be drifted, but a rear wheel drive car which is front engined is the ideal drifter platform. Reducing the weight of the vehicle is also a big help in drifting. It allows the car to be more responsive, changing direction easier, and slides and handles more controllably. This is one reason light weight rear wheel vehicles like the AE86 are ideal for this application.
Just as soft suspension helps drags cars to hook their power up, a stiff suspension will create wheel spin. Stiff suspension in a drifter is what is needed to make breaking traction easier. Different cars and different drivers will demand varied preferences and this is why adjustable suspension is so prevalent in the drift scene. That being said a certain level of stiffness is desired in all drift cars. If you go too soft, the rear will be hard to break traction. But going as stiff as a race car is not necessary; a faster rebound rate will help when sliding.
A hard set of springs and shocks will grant the chassis an uprated level of stiffness. But this will usually not be enough for controllability. Strut braces are a great way to increase the chassis stiffness. Swapping bushes for a set of polyurethane ones will also greatly improve the stiffness and controllability of the suspension. To generate more oversteer if your car isn’t hanging it out enough for your liking, fit a firmer swaybar at the rear. The front wheels will need to be splayed outwards. The front wheel alignment required a decent amount of positive castor to help the vehicle turn in and not understeer. Negative camber needs to be applied also. Both of these set ups are important because they will allow the front wheels to grip through a corner and not understeer. It will also help induce a healthy dose of oversteer for the rear.
The rear tyres, on the other hand, should have as little negative camber as possible. This will render the wheels almost perpendicular to the ground. Such a setting gives the car limited grip through a corner, which is what is needed to achieve a great drift.
One way of looking at a drift set up is the front wheels need to be set up much like a circuit car, while the rear wheels are set up like a rally car but with more stiffness. Lastly a little bit of toe out at the front will help with cornering. Nothing drastic, just 2-4mm at the most.
Circuit Car -
Circuit cars have one simple philosophy in their design and it stands out like a sore thumb when you have a look under their guards. Cornering is what it is all about, and builders of these cars have everything geared to cornering as fast as physically possible.
As a general rule the less grip your tyres have the less camber you dial in. Increased ride height and spring travel along with softer sway bars will increase the traction generated by the tyres you have. In circuit racing traction is much easier to come by. The roads are immaculately smooth and the bitumen is grippy. Circuit cars run ultra soft tyres which wear out extremely quickly but provide very high levels of grip.
The cornering involved in racing means that body roll is a big enemy. This is why you will find that track vehicles have very stiff suspension. The springs and shocks are quite stiff because big bumps and rough ground is not a concern. The are low to drop the centre of gravity which helps with weight transfer. Stiff sway bars, and plenty of negative camber also help with the weight transfer issue. A race car does not want the weight to betransferred in large doses from the right to left or front to back. Limiting weight transfer will allow the inside tyres to work better through a turn. Tyres work better when they are evenly loaded up as opposed to one being loaded heavier than the other. Limiting roll and weight transfer will also help the car from bottoming out in a corner and prevent bumpsteer.
Toe out will make the car turn extremely fast and will rotate rapidly. Stiff springs, shocks and sway bars will assist this also, but a few millimeters of toe out will benefit this immensely. Save toe out for the track though, because it can make the car feel twitchy and wanting to turn at all times.
Ensure that there is enough camber. This time the rear will need some camber also to maintain a certain level of grip through the corners, particularly in a rear wheel drive car. Things such as strut braces and bushes will improve the chassis stiffness and responsiveness of the vehicle. As mentioned in the components section, some race vehicles have no bushes at all between the moving parts, which mean they would be very stiff.
Rally Car – Dirt Track Warrior
Rally is one of the most spectacular visual racing events due of the landscape.
Rally cars are quite different from the rest of the car setups on this list in a number of ways. The reason their suspension is juxtaposed to something like a circuit car is because of the sorts of terrain they traverse. Rally is one of the most spectacular visual racing events due of the landscape. Dirt, ice, snow, sand, gravel; all these surfaces are low grip and this is what creates the awesome thrills and spills that is rally car racing. Some people nothing more exciting than watching a little Swede fling a WRX through a snowy forest.
Low grip coupled with treacherous cliff passes and trees and rocks surrounding the track dictate a need for as much traction as physically possible. It is inevitable that the car will slide around the track, but they are controlled slides and this is an amalgamation of a number of techniques.
If you take notice of a rally car, you will see they do not sit low like a circuit racer. A standard ride height is good, sometimes even higher. This way suspension travel is maximised to absorb the rough ground, bumps and jumps. A good quality shock absorber is paramount in rally as they cope a good hiding. But don’t expect them to last for a long time anyway. The thrills and spills in rally ensure that the shocks are beaten to within an inch of their life.
The spring rates in a rally car are just as important as the shock absorber. Soft springs are a better choice as you really want the rubber under the car to stay in contact with the rough roads. Stiff springs will make the car skip over the bumps and not absorb them which equals poor traction. Sway bars are also going to have a thinner profile, endowing them with more give and softness to make sure the handling is compliant and willing to follow the contours of the ground. For a rear wheel drive rally car, making the rear springs soft is essential for grip. Not only will the rear end be delivering power, it will also be hanging it out for most of the journey. The softer the spring, the more grip the tyres will exert.
Castor for the front wheels is important to enhance turn in. One thing you have to be aware of is the camber. Too much negative camber on gravel is not ideal because the front wheel grip will be compromised for turn in. Seeing a rally car is just as likely to slide as it is to dig in and grip through a corner, massive negative camber would be a bad match for the soft swaybars.
Show Car - Exhibit Queen
Building a car for show is all about looks. Bright paint, big chrome wheels, detailed engine bay and trimmed interior is what gets you the looks, and maybe some girls if you are really optimistic. Rolling the guards to ensure those 20+inch rims fit under the guards is essential. This will limit the rubbing that will wear away those high profile tyres when you are driving every day. But never fret; throw a few mates in the car and there will be enough tyres scrubbing going on to allow you to look cool in front because you have such a low car.
There are a few ways to lower your car for show action. The easiest is finding the lowest springs you can, and then cutting them in half with an angle grinder, or getting your local spring maker to fashion some super low springs that can be fitted under your ride. Stock shocks coupled with ultra low, miss-matched springs are the ideal way to go when you need a low show car. Now that airbags are making a name for themselves they are a convenient option which will allow you to cruise in practicality but drop the ride to the floor when at a show. The cost can be prohibitive to some people and that is why some of the more classic and grass roots options are still floating around. Sometimes it is good to remember our roots.
If you really want to impress some people, just take out your springs all together. It wont matter if the spring can fall out when the shock is at full extention, because you wont be driving your awesome show car on anything that resembles a piece of blacktop anyway. Hell why not even take out the shocks too and have the chassis riding on the bump stops. This way the spring and the shock can be safely stashed away at home. You don’t need to worry about anything falling out because there is nothing to fall out… oh except your teeth due to the slightly firm ride. Statisical information tells us that the ‘wheel deep into the guard’ look is the sh*t so it is worth it anyway.
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