Anti Lag	Blancing	Blow Off Valve	Boost Controller
Catalytic Converter	Clutch	Detonation	Drivetrain
Flywheel	Head Work	Intercooler	Manual Transmission
Rotors	Turbo	Turbo Timer	Water Injection

Put simply boost controllers work by "tricking" the actuator (which controls the wastegate) into believing a lower boost level is being generated. This allows the turbo to generate more boost as the wastegate opens later. The best boost controllers allow the actuator to see no boost until full boost is reached, thus avoiding wastegate creep (described below).

    The wastegate is a "flapper valve" which controls the amount of exhaust gas which is redirected around instead of through the turbocharger. When the wastegate is shut, all exhaust gas from the engine will be channeled through the turbo - with it open, a certain amount will pass straight from the engine to the exhaust system, by-passing the turbo. Turbo speed - and output pressure - is thus indirectly controlled by this valve. Without a wastegate, boost levels would skyrocket to the maximum capacity that the turbocharger could produce, which is usually greater than what the engine can handle. Wastegate are controlled by an actuator which is fed manifold pressure. This opens when the spring inside it is overcome by pressure, and opens the wastegate. Under pressure, the actuator rod extends to open the wastegate valve in the exhaust side of the turbo. When the boost pressure and internal spring pressures are in balance, boost will be maintained at that level.