Your Guide to Suspension Set-Up
When it comes to suspension upgrades & set-up, there is a variety of products and services from all over the world on offer from your local performance and tyre specialists. At Lohen, we understand that choosing the right product for you and your MINI is important. Once you choose your new suspension parts, getting the perfect set-up is crucial in order to get the most from the new upgrade(s). Here is a short guide to explain all the areas of adjustment and what they do for your MINI.
MINI's Stock Suspension
The MINI's stock suspension is pretty good for a standard production car, offering the go-cart handling many are so fond of, but it offers almost no adjustment. It can be vastly improved to suit your personal styling and performance preferences and set-up with a few choice upgrades. The MINI suspension is considered to be great on smooth, flat, track like roads, however as most roads are not flat, more and more of us are having to deal with potholes and uneven road surfaces on our commute to work. Upgrading the MINI's suspension is relatively easy and a few simple modifications can improve the looks, handling characteristics and the ride quality, making you fall in love with your MINI all over again.
Suspension Set-Up
The main role of any cars suspension is to keep the tyres of the car in contact with the road surface over all types of surfaces for as long as possible while optimising the amount of contact the tyre has with the road. So getting the correct set-up is crucial to ensure good grip in all types of conditions and surfaces. Provided the appropriate components are installed, the main areas of improvement and adjustment are:
- Camber
- Caster
- Tracking/alignment
- Ride height
- Damping rates – Bump and Rebound
- Corner weighting
- Anti-roll bar stiffness
Outside of direct suspension components, handling behaviour of the car can also be affected by the following components:
- Tyres
- Suspension Bushes
- Strut and/or Body Braces
- Roll cages
We will explain each one of these in greater detail now.
What is Camber? 
Camber is the angle at which your wheel and tyre stand in relation to the road. When cornering the contact patch between the tyre and the road is significantly reduced due to body roll. In order to maximise the amount of contact between the tyre and the road, it is important that the camber angles of your suspension are adjusted correctly. This can be done for both front and rear wheels.
Neutral Camber
If your wheel and tyre are sitting completely perpendicular with the road then the camber angle is set at 0 degrees, this is known as neutral camber (or no camber). Neutral camber is best for maximum acceleration and braking as it maintains a flat contact patch with the road when the car is moving perfectly straight ahead. However, the perfect camber angle for cornering actually sees the wheel tilted slightly (negative camber) to account for the forces that are imparted on the wheel while your MINI is cornering.
Positive Camber
Positive camber is where the wheels and tyres of your car lean outward from the top. This means that the outer edge of the tyre has the most contact with the road especially when it encounters a turn. When positive camber is set, the tyres wear out faster on the outer edge and the car does not make full use of the potential available grip with the road.
Negative Camber
Negative camber is often visually apparent as the wheels and tyres begin to tilt inwards towards the car. This form of camber is becoming increasingly popular because of its visual appeal (think stance cars with wide-stretched tyres), however, the real benefits of negative camber are seen in the handling characteristics. If the wheels on your car are set with a negative camber angle, those of you that might be more spirited drivers will see increased grip when cornering heavily, as the tyre will maintain a better contact patch with the road. This should allow you to carry a higher speed through a corner. When driving in a straight line, the negative camber can reduce the surface contact between the tyre and road and hence you lose traction easier when braking or accelerating hard. So the trick with negative camber is to get the balance right between maximum in-corner performance and straight-line acceleration and braking as well as tyre wear. Typically, a fast road set up will have -1 to -2.5 Degrees and a track or race set up -3 to -5 Degrees. A downside of too much negative camber can be noticed when a car tramlines down the road, this is because the front wheels become “stuck” in the groves that heavier vehicles have left in the road (i.e. in lanes 1-2 of the motorway from trucks). Further problems can arise if you do a lot of “straight line” driving (i.e. dual carriageway or motorway) as the inner edges of the tyre will wear more than the outer edges and the centre of the tyre. This happens because the wheels are remaining constantly at negative camber and all the pressure is on the inner edge of the tyre.
What is Caster?
The caster angle on a car has the ability to centre itself under the cornering loads and it is the angle created by the steering’s pivot from the front to the back of the vehicle. If the caster line is angled forward it is negative and if it’s angled backwards it's positive. Improper caster adjustments will make your MINI difficult to keep in a straight line.
Positive Caster
Positive caster angles are more likely to produce a self-centring action of steering, leaving the base of the tyre pointing inwards. On a road, this means that the top coilover would be pushed towards the rear end of the car. Positive caster angles create a lot more aligning torque which improves the straight-line stability of the car. A large positive camber angle is good for high-speed stability but can make it more difficult when steering. It is important to remember that positive caster will increase negative camber gain when turning and on the whole, most cars with power steering want as much positive caster as they can get, as it provides the car with a better steering response and can improve the car's stability at high speeds.
Negative Caster
Negative Caster is where the steered wheel (i.e. the front wheel) is behind the vertical axis and is normally only found on older cars due to their tyre technology and chassis dynamics. Negative caster often makes the steering wheel feel light whilst forcing your car to wind down the road without proper direction. It is important to remember that caster settings across angles should be symmetrical as applying different degrees to either side of your car can make it pull towards one side or the other, this is will be especially apparent on the side that has the least amount of caster.
What is tracking?
Wheel alignment, which is sometimes referred to as ‘tracking’ or ‘toe’ is the term used to describe the angle of the wheels in relation to the vehicles forward movement. Its purpose is to reduce tyre wear and to ensure the vehicle travels straight and true without the car pulling to one side. The car's manufacturer usually sets the alignment angles but they can be altered beyond the maker’s specifications to obtain a specific set of handling characteristics.
What causes your car to need wheel alignment?
There are several different reasons as to why your wheels may need re-aligning; some of the most common causes are listed below:
- Sudden impact – the wheels can become misaligned if certain components get damaged, this is often caused when you hit a pothole, the curb or if you are involved in a road accident.
- Wear and tear of parts – over time parts like your suspension springs, ball joints and bushes can become slack or worn, which can lead to a shift in the wheel alignment
- Suspension modifications – modifying your car's suspension can also affect the alignment of the wheels. A car's suspension is designed to work at a certain height, so if you adjust the height of your vehicle without adjusting the suspension then your wheels could become misaligned.
What are the symptoms of misaligned wheels?
Identifying if your wheels are misaligned is important as improper wheel alignment can affect how your car handles, cause uneven tyre wear and can make your car unsafe for driving. Symptoms:
- Abnormal or uneven tyre wear – if one of your front or back tyres is showing a different wear pattern than its opposite, then more often than not this means your wheels are misaligned.
- Pulling to the left or right – If your MINI's wheel alignment is sufficiently out, you will probably notice that your car will automatically turn to one side or the other. If you are having to constantly wrestle with the steering wheel then it's probably time you for your wheels to be realigned so all the wheels point in the right direction.
- Passive Pulling – if your vehicle isn’t actively pulling then its unlikely that there is a problem with your wheel alignment, however, if you let the steering wheel go when you're on a straight road and your car drifts off to one side then your wheels may need realigning. This may also be due to other features such as a differential etc.
- Vibration – bad wheel alignment can also cause vibrations as the wheels on your car pull against each other. If your car is shaking when you drive down the road then it might be an idea to get your alignment and wheel balancing checked.
- Crooked Steering Wheel – If your steering wheel is crooked or at an angle but you are travelling straight ahead, this may also mean that your wheel is misaligned, however, it could be that the steering wheel was not centred when the wheel alignment was carried out.
What is Corner Weighting?
Corner weighting or as its also known ‘corner balancing’, is the process whereby the car's suspension is adjusted until the diagonal weight distribution across all the tyres is even. The diagonal weight or ‘cross weight’ on the left front and right rear side should be the same as the right front and the left rear, meaning that the weight of the car is split 50/50 with each side. Having a car with as near to equal weight distribution as possible has a number of advantages, it increases the cornering balance and handling characteristics while providing balanced acceleration and braking. However, if your cars diagonal weights are not equal then its handling could be unbalanced and it will turn better one way and not the other. If your car does have an unequal weight distribution it can result in a tyre or all the tyres being overworked meaning their grip levels will drop, as this increased pressure and heat build-up it can cause your tyres to wear prematurely. While corner weighting is not something everyone will need to do if you are looking to compete on the track it may give you an advantage over your competitor when it comes to the handling. If you are looking to track your car then having the correct weight distribution for your car is something that is certainly worth investigating.
How do I go about setting up my car?
If you are looking to get your MINI's suspension set up correctly, Lohen is the place to go – we offer height adjustment options, camber adjustment options, corner weighting and damper set up for all units that offer adjustability and our expert team will work with you to achieve your perfect set up! However, remember that most of these adjustments are NOT possible if your MINI has stock suspension.
- Adjustable ‘Top Mounts’ are required to optimise Front Camber
- Adjustable ‘Rear Arms’ are required to optimise Rear Camber
- Adjustable spring platforms are required for ride height and corner weight adjustments
- Caster Bushes are required to alter caster angles.
To book in call us on 01785 859999 or email sales@lohen.co.uk.