Car tuning is both an industry and a hobby, in which a car is modified in order to improve its performance and handling and improve the owner's driving style. As most cars leave the factory set up for average driver expectations and average conditions, tuning has become a way to personalize the characteristics of the vehicle to the owner's preference. For example cars may be altered to provide better fuel economy, produce more power at high RPM or the ride comfort may be sacrificed to provide better handling.
Car tuning is related to auto racing, although most performance cars never compete. Rather they are built for the pleasure of owning and driving such a vehicle. Another major facet of tuning includes performance modification to the car exterior. This includes changing the aerodynamic characteristics of the vehicle via side skirts, front and rear bumpers, adding spoilers, splitters, air vents and light weight wheels.

Areas of modification


Car Audio

Is a term used to describe the sound or video system fitted in an automobile. A stock car audio system refers to one that was specified by the manufacturer when the car was built. A custom car audio installation can involve anything from the upgrade of the radio to a full-blown customization of a car based around its audio equipment. Events are held where entrants compete for the loudest or most innovative systems.

Engine tuning



Engine tuning as of late has been marketed as the replacement of basic engine components with after-market versions that perform the exact same functions as those replaced while promising an increase in power output. Car tuners usually install new turbochargers, modify the car's engine cooling unit, replace the air filters but they could also install a more powerful engine on the cars they modify.

Suspension tuning

Suspension tuning involves modifying the springs, shock absorbers, sway bars, and other related components of a vehicle. Shorter springs offer an improved lowered look and a lower center of gravity. Stiffer shock absorbers improve the dynamic weight shifting during cornering, and normally have shorter internals to stop them from bottoming out when shorter springs are used. Stiffer away bars reduce body roll during cornering, thus improving the grip that the inside tires have on the surface; this improves handling response. Other components that are sometimes added are atrust bars which improve the body stiffness, and help better maintain the proper suspension geometry during cornering. On some cars certain braces, anti-roll bars, etc, can be retro fitted to lower spec cars from sports models.
For off road vehicles, the emphasis is on lengthening the suspension travel and larger tires to increase ground clearance.
Low riderswith hydraulic/pneumatic suspensions use another unique kind of suspension tuning in which the height of each individual wheel can be rapidly adjusted by system of rams, even to the extent that it is possible to "bounce" the wheels completely clear of the ground.

Body tuning

Body tuning involves adding or modifying spoilers and a body kit Sometimes this is done to improve the aerodynamic performance of a vehicle, as in the case of some wings or bumper canards, or, to lighten the vehicle through replacing bodywork components such as hoods and rear view mirrors with components made from lighter composites such as CRFP. Cornering speeds and adhesion can be improved through the generation of down force.
More often however, these modifications are done mainly to improve a vehicle's appearance, as in the case of non-functioning scoops, wide arches or any aesthetic modification which offers no benefit to performance. Very rarely does an after market body kit improve performance, the majority add weight and increase the drag coefficient of the vehicle and thus reduce its overall performance.
Increasing the wheel track width through spacers and wide body kits enhance the cars cornering ability. Lowering the center of gravity is another aim of body tuning dealt with via suspension modifications.

Detuning

Detuning involves returning a modified car to its original factory status. It is akin to automotive restoration. The term Detuning can also refer to the reduction or decrease of performance in a particular area of tuning. An example of this could be where the engine tune is "detuned" to allow for increased traction on a day where the track grip is not sufficient.

Terms

"Streeted" or "Tuner Cars" are Japanese imports, such as a Toyota Supra, Mazda RX-7, Subaru Impreza, and the Mitsubishi Lancer Evolution series. These cars are most commonly modified with the more expensive mods available. The most popular modifications include suspension upgrades, exhaust systems, and turbos.

Legal requirements

Many countries have legal requirements in regard to what car owners can and can't do in relation to vehicle modifications. For example, all vehicles in Victoria, Australia, must conform to construction standards to ensure vehicles provide drivers and passengers with a maximum level of safety. There are also restrictions for P Plate drivers which can prevent young drivers from driving modified vehicles.
In the United Kingdom and the Netherlands it is illegal for any car to have blue lights as they are used by the emergency vehicles.
In Scotland and Denmark, it is illegal for any car to have neon under lights on a car as it distracts other drivers. In the Netherlands neon is allowed under the car but only when the car is on display, if the car is on a public road the lights have to be switched off.
Recently, Belgium issued a new law which describes that body kit parts need to be approved for safety issues.