Automotive turbochargers significantly improve the performance of a vehicle's engine while in most cases retaining the vehicle's handling. Turbochargers operate by turning an impeller to draw fresh air through the vehicle's air filter and increase the atmospheric pressure of the air in the vehicle's combustion chamber. Turbocharger systems for cars are often very expensive and in many cases require professional installation and tuning of the vehicle to work properly. These are not, however, the only disadvantages to turbochargers.
Turbo lag is a problem that is encountered by practically every turbocharger system installed on cars. This is defined by the amount of time it takes for the turbocharger to build sufficient pressure in the combustion chamber of the vehicle before the full potential of the vehicle's performance is realised. Careful timing is necessary in racing applications to avoid turbo lag at the wrong time. It can send the vehicle out of control, particularly in tight corners where tire grip is already compromised.
Improperly installed turbocharger systems have an extremely damaging effect on the engine onto which they are mounted. Turbochargers are rated according to the amount of air they deliver in pounds per square inch (PSI). Most cars and trucks work efficiently with additional power and only minor tuning between five and seven PSI. Levels of eight to 12 PSI often require reinforced internals such as a heavy-duty valve train and special pistons. Turbochargers functioning above 12 PSI often require professional engine modification to prevent serious damage to the engine block and internal components. In some cases, properly installed and tuned turbocharger systems that are negligently driven will still fail and permanently destroy the vehicle's engine.
A turbocharger used without an intercooler can create extremely high heat in the engine compartment of the vehicle. This additional heat can lead to overheating breakdowns, melting of critical plastic engine components and fires. Using an intercooler mitigates this problem, but is an expensive addition to the system. Intercooler systems are not always sold in kit form with the turbocharger.
Installing an aftermarket turbocharger on any vehicle still under manufacturer's warranty can invalidate the vehicle warranty in its entirety. Turbochargers are considered off road racing equipment and most vehicle are not designed to use them. Your warranty will be invalidated and you will have to pay for repairs out of pocket if the damage to the vehicle is caused by the turbocharger.
Vehicles with turbochargers are much more expensive to insure than vehicles without turbochargers installed. The difference is much more significant for teen drivers who possess turbocharged vehicles, at times as much as doubling the standard insurance premium.