Treg

How cars handle on the road

While handling might not be the most important consideration when it comes to purchasing a vehicle, having a car that can deal with different driving scenarios is important. Blind corners on winding country roads or swerving to avoid potential dangers can have serious consequences. Your car could spin out of control, hit another motorist or come off the road altogether. The way your car handles and grips the road surface will depend on several factors, so here are some of the most significant things to think about.

Weight distribution

When a car goes round a corner, there will be a transfer of weight from side to side that causes body lean. This is also apparent when a vehicle accelerates or brakes, as the downward load will transfer between the front and rear tyres. The best performing vehicles, such as sports cars and performance hatchbacks, have a lower centre of mass, as less weight is being thrown around. Taller vehicles like 4x4s and SUVs do not handle as well, as the weight and high centre of mass puts a lot of pressure on the tyres. The position of the engine in all cars will make a difference too. Cars with an engine in the front tend to understeer, while rear-heavy vehicles usually oversteer. This is why a lot of performance vehicles utilise a mid-engine design in order to achieve an ideal centre of mass. Several manufacturers pursue '50/50' weight distribution, although this is not always possible, as certain automakers prioritise seating comfort, passenger legroom and ample room for luggage. Carrying around excess and unnecessary weight in your car is detrimental to the handling. So if you want a better driving experience in the corners, remove surplus objects from the boot or interior.

Suspension

Suspension is the system of springs, shock absorbers and linkages that connects the vehicle to its wheels. This makes a huge difference in how the car rides and handles. Depending on the type of vehicle, manufacturers will set-up the suspension for either a smooth ride or responsive handling.

Important properties associated with suspension include:

Shock absorbers - These dampen the motions of a vehicle moving up and down on its springs by absorbing energy.
Spring rate - This will determine the vehicle's ride height or its location in the suspension stroke. When the spring is compressed, the force it exerts is proportional to its change in length. Hard springs are better for handling, as the body will not roll as much.
Damping - The control of motion or oscillation usually found with hydraulic gates and valves in the vehicle's shock absorber.
Travel - The distance from the bottom of the suspension stroke to the top is usually shorter for cars that handle well, but off-road vehicles require large travel points to deal with rough and varied terrain.
Camber - The angle made by the wheels of a vehicle. Negative camber improves grip when cornering because the tyre is at a better angle to the road.
Roll centre height - The point where cornering forces in the suspension are reacted to the vehicle body. This is usually determined by the car's centre of mass.

Nearly all car manufacturers have models with fully active suspension systems, which electronically monitor vehicle conditions and adjust the set-up accordingly. It is also possible for the driver to select the most appropriate suspension set-up depending on personal preference.

Aerodynamics

A vehicle's body shape and exterior features will affect its aerodynamics, which also impacts on handling. This makes the biggest difference when a car is travelling quickly, as forces are generally proportional to the square of air speed. Measures are taken to compensate for the inevitable increase in oversteer that comes with quick cornering speeds too. Car designers concentrate on making cars as streamlined as possible to reduce drag and will include spoilers or intakes to increase downforce and reduce negative lift, which improves handling. While this is more common among performance vehicles, several passenger cars adopt these aerodynamic characteristics to counteract the tendency of positive lift. The majority of automakers will now design and develop cars with advanced wind tunnels and computational fluid dynamics (CFD) to improve and optimise aerodynamics. Along with handling, the way a car cuts through the air also has a positive or negative impact on acceleration, speed and fuel economy.

Wheels and tyres

A car's entire braking, acceleration and cornering performance have to be translated through the tyres, so maximising traction is crucial. While this is affected by suspension design, the type, pressure and tread of a tyre make a significant difference too. Generally speaking, larger tyres with soft rubber and stiff cord configurations increase grip and improve handling. Ideally, tyres should be soft enough to conform to the road surface, but hard enough to last for a long time. Increasing a tyre's pressure will reduce the slip angle and result in better handling. However, reducing the contact area is detrimental to braking and can be dangerous on unusual or poor surface conditions, so this should be carried out with caution. It is advisable to have a different set of summer and winter tyres if the temperature and climate differs greatly between seasons.

Weather conditions

Driving in adverse weather conditions such as torrential rain, heavy snow or surface ice can dramatically affect handling. Slippery conditions will reduce traction and grip, causing motorists to lose control if they are travelling too quickly. If the car starts to skid, the driver is best advised to turn the wheel in the direction they want to go. One of the most common problems in wet weather is aquaplaning, where a car drives over a deep patch of water without the wheels reaching the road surface. This tends to happen if the depth of tyre tread is too low. Snow and ice requires a gentle approach, as stopping distances are up to 10 times longer. Avoid stopping when going up a hill and keep a constant speed. A high gear will stop wheels from spinning as they try to find grip. On the way down, using the engine to slow down with a low gear will prevent brakes from locking up and skidding.

The driver

Although car manufacturers and automakers do everything they can to ensure handling is the best it can possibly be, it ultimately comes down to the driver behind the wheel. In the first few months of owning a new car, it may take some time for the driver to get used to how the vehicle handles. There is the possibility that the suspension, aerodynamics and steering is different to what the individual is used to. While these can sometimes be adjusted, free rotation of the steering wheel before the wheels rotate, known as play, is a common problem that requires professional repair. The seating position can also make a difference to handling, as a driver moving around behind the wheel as a car undergoes rapid acceleration, aggressive cornering or sharp braking may not be in full control. Good back support and staying within reach of all the controls is highly advised. Thankfully, if a motorist feels they need educating or additional driver training , there are numerous courses available. Pass Plus is a six hour practical driving course that aims to improve driver safety and ability. Although it is more applicable for drivers in the year after passing their test, the course can be taken at any time. Pass Plus covers driving in town, in all weathers, on rural roads, at night, on dual carriageways and on motorways. Driving courses from the Institute of Advanced Motorists are quality assured by the Driving Standards Agency and aim to help improve a motorist's skills, anticipation and enjoyment behind the wheel. According to 2500 people who passed the Advanced Driving Test, 99 per cent said it improved their driving, 90 per cent had a greater awareness of other road users while 66 per cent managed to avoid a crash because of the course.

Trailers and caravans

There are restrictions on the size and weight of caravan or trailer you're allowed to tow depending on your license. However, in all circumstances, extreme care must be taken, as towing will have an impact on handling. First and foremost, you won't be able to travel at the same speeds as normal with a caravan or trailer. Using an undersized or underpowered towing vehicle will result in poor handling and could cause an accident. The same can also be said with a poorly balanced or overloaded caravan. Sometimes a caravan or trailer will begin to swerve from side to side when travelling in a straight line. To stop this, ease off the accelerator to slowly and calmly regain control. Braking or steering heavily will make the problem worse and you could lose control altogether.