Impreza-WRXSTi-EJ20-EJ25-TD05H-18G-Turbocharger-wWastegate-Turbine-AR-49--30-psi-Boost-Controller-Purple

Turbocharger:
The objective of a turbocharger is to improve the engine's volumetric efficiency by solving one of its cardinal limitations. A naturally aspirated automobile engine uses only the downward stroke of a piston to create an area of low pressure in order to draw air into the cylinder through the intake valves. The pressure in the atmosphere is no more than 1 atm (approximately 14.7 psi), so there ultimately will be a limit to the pressure difference across the intake valves and thus the amount of airflow entering the combustion chamber. Since the turbocharger increases the pressure at the point where air is entering the cylinder, a greater mass of air (oxygen) will be forced in as the inlet manifold pressure increases. The additional air flow makes it possible to maintain the combustion chamber pressure and fuel/air load even at high engine revolution speeds, increasing the power and torque output of the engine.

Boost Controller:
A manual boost controller is a simple mechanical and pneumatic control to allow some pressure from the wastegate actuator to escape or bleed out to the atmosphere or back into the intake system. This can be as simple as a T-fitting on the boost control line near the actuator with a small bleeder screw. The screw can be turned out to varying degrees to allow air to bleed out of the system, relieving pressure on the wastegate actuator, thus increasing boost levels. These devices are popular due to their negligible cost compared to other devices that may offer the same power increase.

This Product Compatible with:
02-11 Subaru Impreza WRX/ STi (GD/ GE/ GH8)

Modification would be Required for Models Below:
05-11 Subaru Legacy GT (Including Spec. B) (BL/ BP/ BM/ BR)
04-11 Subaru Forester XT/ Sports 2.5 XT (SG/ SH)
05-09 Subaru Outback III XT (BP)
***Fits Models with 2.0L/ 2.5L 02-11 EJ20 and 04-11 EJ25 Engines ONLY