Car tuning is both an industry and a popular hobby, in which a car is modified i
n 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.
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 w
hile promising an increase in power output.
Tuning an electronically controlled management system is only necessary when major components of the engine have been changed. For example, fuel injectors have a limitation on how much gasoline can be supplied to the combustion process. If you turbocharge your vehicle, the turbocharger forces more air into the cylinders than they are capable of drawing in on their own, which requires fuel injectors with a much higher flow rate to compensate with the proper amount of fuel. The ECU however will apply the stock fuel map to the new injectors as if they were the originals, causing too much fuel to be sprayed. In this condition the car will not run well, or at all. This is where legitimate tuning comes into play. There are a variety of computerized products available to handle significant changes like this, ranging from Air/Fuel controllers, to piggy-back ecu's, to completely replacing the original system with an advanced 100% customizable stand-alone management system.
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. 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.
"Pimped" cars are usually referenced to classic cars.
"Streeted" or "Tuner" cars are Japanese imports, such as a Toyota Supra or 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.
n 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.
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 w
hile promising an increase in power output.Tuning is, on modern fuel injected engines, the electronically controlled management of ignition and injector timing & spray duration to achieve a desired, well burning ratio of air and fuel. The car's engine control unit (ECU) dictates these actions according to the constantly changing information fed to it from a variety of sensors located up and downstream of the combustion process. There is a sensor in the intake stream which measures the density/quantity of oxygen entering the engine, as well as a sensor in the exhaust stream to measure how much of it was used during combustion. The engine's operating temperature (and often intake air temperature) is also measured, the values of which are all used in computing a tune to maintain the manufacturers specific target fuel-to-air ratio.
Tuning an electronically controlled management system is only necessary when major components of the engine have been changed. For example, fuel injectors have a limitation on how much gasoline can be supplied to the combustion process. If you turbocharge your vehicle, the turbocharger forces more air into the cylinders than they are capable of drawing in on their own, which requires fuel injectors with a much higher flow rate to compensate with the proper amount of fuel. The ECU however will apply the stock fuel map to the new injectors as if they were the originals, causing too much fuel to be sprayed. In this condition the car will not run well, or at all. This is where legitimate tuning comes into play. There are a variety of computerized products available to handle significant changes like this, ranging from Air/Fuel controllers, to piggy-back ecu's, to completely replacing the original system with an advanced 100% customizable stand-alone management system.Air/Fuel controllers are commonly used to "lean" or "richen" an air/fuel mixture, by modifying the signal coming from the air intake oxygen density sensor mentioned earlier. By modifying the signal, the ECU receives a higher or lower voltage signal than actual, and compensates with a bit more or less fuel to achieve your desired result. "Piggy-back" computers work much in the same way, but they allow you to work with most other sensor input values, and more specifically allow you to control fuel flow rate and ignition timing by applying variations against the stock ecu's map. A stand alone computer system is similar in function to a piggy-back, but is significantly more advanced and replaces the stock computer altogether, requiring a completely custom map, and is used mostly for race applications. Any of these kinds of products require a specialist who understands engine tuning to produce safe results. In most cases a dynamometer is used to measure the effect of changes made and provide a way to determine exactly how much power your tune is making.
Suspension tuning
Suspension tuning involves modifying the springs, shock absorbers, swaybars, 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. Stiffer sway bars reduce body roll during cornering improving the grip that the inside tires have on the surface thus improving handling response. Other components that are sometimes added are strut bars which improve the body stiffness and help better maintain the proper suspension geometry during cornering.
For offroad vehicles, the emphasis is on lengthening the suspension travel and larger tires to increase ground clearance.
Lowriders with 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. 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.Another common body modification is called "shaving" or "flushing". This involves removing 
door handles, bumpers, emblems, chrome trim pieces and key locks. The reason for this is to make the appearance of the car look smoother and cleaner with less disruptions on the body lines. The doors and trunk are alternately opened with keyless remote.
Another popular major body modification is to alter the way in which the doors open. Examples include Scissor doors (or "Lambo doors") and Suicide doors. "Lambo doors" open outwards until clear of the body of the vehicle and then rotate upwards. Suicide doors open in a similar way to conventional doors except that they are hinged at the rear edge of the door and therefore open in the opposite direction. Most of these modifications are done with aftermarket kits which have become commonly available due to the large increase in demands for such parts in recent years. The hood and trunk can also be modified to open differently, a very common modification in the case of large car audio systems being installed within the trunk of the vehicle.
door handles, bumpers, emblems, chrome trim pieces and key locks. The reason for this is to make the appearance of the car look smoother and cleaner with less disruptions on the body lines. The doors and trunk are alternately opened with keyless remote.Another popular major body modification is to alter the way in which the doors open. Examples include Scissor doors (or "Lambo doors") and Suicide doors. "Lambo doors" open outwards until clear of the body of the vehicle and then rotate upwards. Suicide doors open in a similar way to conventional doors except that they are hinged at the rear edge of the door and therefore open in the opposite direction. Most of these modifications are done with aftermarket kits which have become commonly available due to the large increase in demands for such parts in recent years. The hood and trunk can also be modified to open differently, a very common modification in the case of large car audio systems being installed within the trunk of the vehicle.
This section of vehicle modification has now by far the largest market share of aftermarket parts throughout the world , with a vastly extensive option of parts available for example neon under body lights, tinted windows, Iridescent and "Flip Tone" paints, Body Decals and Custom Shaped Muffler tips. Essentially every conceivable form of aesthetic modification is now possible and widely available allowing for each owner to customise their vehicle right down to their very own personal specifications and tastes without entering the realm of more complicated, mechanical modifications associated with engine and suspension tuning.
Detuning
Detuning involves returning a modified car to its original factory status. It is akin to automotive restoration.
Terms
"Pimped" cars are usually referenced to classic cars.
"Streeted" or "Tuner" cars are Japanese imports, such as a Toyota Supra or 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. The construction standards are contained in the Vehicle Standards Information Bulletins. There are also High Powered Vehicle Restrictions for P Plate drivers which can prevent young drivers from driving modified vehicles.
In the United Kingdom 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 underlights on a car as it distracts other drivers. In Holland 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 bodykit parts need to be approved for safety issues.
Sanctioning organizations
Many organizations involved in competitive motorsports establish safety guidelines that far exceed legal requirements when viewed in terms safety. The NHRA, IHRA and SOLO programs all require that vehicles pass inspection to ensure that all regulations are being complied with.
